title: VI, 3. Molecular biology and epidemiology of Aichi virus and other diarrhoeogenic enteroviruses

text: The virion of the Aichi virus contains a single-stranded RNA molecule as the genome. The homology of Aichi virus structural proteins (VP0, VP3, and VP1) with corresponding polypeptides of other picornaviruses varies between 19% and 32%. The epidemiology of the Aichi virus as a medically important pathogen has not been well defined. Stool samples from adult patients in six oyster-associated gastroenteritis outbreaks were examined for variation, based on their reactivity with a monoclonal antibody raised against the standard strain (A486/88) and on reverse transcription–polymerase chain reactions (RT-PCR) of three genomic regions. Antibody to the Aichi virus could be detected using a neutralization test and an enzyme-linked immunosorbent assay (ELISA). These methods were used for the identification of Aichi virus infection in paired serum samples. The chapter concludes with a discussion on other diarrheagenic enteroviruses.


The disruption of infectious bronchitis virus (IBV-41 strain) with Triton X-100 detergent


Immunoblotting and dot blotting


title: Effects of immunopotentiating agents on alveolar macrophage properties

text: Infectious respiratory diseases in man and in domestic animals are characterized by the presence of a large number of different microorganisms: viruses, bacterias, mycoplasmas. It is therefore necessary to stimulate non-specific defense mechanisms in the lung and especially alveolar macrophages (AM). These cells, located in the alveolar air-spaces, play a major role in the lung clearance mechanisms and exert antibacterial, antiviral and antitumoral activities. Activation of alveolar macrophages was studied in vitro with lipopolysaccharide (LPS), lymphokines or mycobacterial derivatives (MDP). Rodent alveolar macrophages were rendered cytotoxic by in vitro exposure to LPS, free MDP or liposome-encapsulated MDP derivatives. In vivo, intravenously administered liposomes containing lipophilic MDP derivatives induced cytotoxic alveolar macrophages and protected mice against the development of pulmonary metastases.


title: Ambisense Rna Genomes of Arenaviruses and Phleboviruses

text: This chapter reviews the evidence that shows that arenaviruses and members of one genus of the Bunyaviridae (phleboviruses) have some proteins coded in subgenomic, viral-sense mRNA species and other proteins coded in subgenomic, viral-complementary mRNA sequences. This unique feature is discussed in relation to the implications it has on the intracellular infection process and how such a coding arrangement may have evolved. The chapter presents a list of the known members of the arenaviridae, their origins, and the vertebrate hosts from which isolates have been reported. It discusses the structural components, the infection cycle, and genetic attributes of arenaviruses. In order to determine how arenaviruses code for gene products, the S RNA species of Pichinde virus and that of a viscerotropic strain of LCM virus (LCM-WE) have been cloned into DNA and sequenced. The arenavirus S RNA is described as having an ambisense strategy, to denote the fact that both viral and viral-complementary sequences are used to make gene products. The chapter discusses the infection cycle, the structural and genetic properties of bunyaviridae member.


Science in a Time of Crisis


title: Viral-Bacterial Synergistic Interaction in Respiratory Disease

text: Humans and animals are constantly inoculated with various microorganisms resident in the upper respiratory tract and by inhaled aerosols, yet pneumonia is a relatively rare event. This implies the existence of very efficient defense mechanisms that are capable of eliminating the vast majority of microorganisms before they colonize and multiply to sufficient levels, resulting in clinical diseases. In order to overcome this continuous barrage of microorganisms, there is a complex array of defense mechanisms present in the upper and lower respiratory tract capable of eradicating these organisms. However, in individuals suffering from a variety of diseases, including virus infections, colonization occurs rapidly with subsequent development of pneumonia. Thus, it is estimated that 90% of bacterial pneumonias develop after a viral infection. Furthermore, individuals suffering from a viral pneumonia have a 40% chance of developing bacterial pneumonia. The reasons for the increased colonization of the lung by bacteria following virus infections are related to the surface properties of epithelial cells lining the respiratory tract, the physiological environment of the respiratory tract, and the alteration of the specific and nonspecific defense mechanisms of the lung that occurs as a result of virus infection.


title: Viral Enteritis

text: Viral enteritis, rotavirus enteritis in particular, has emerged as the major cause of infant diarrhea throughout the world. A new understanding of the causes and mechanisms of viral diarrhea has provided the basis for new approaches to active and preventive therapy. The administration of rational oral fluids and early provisions of nutrients have been beneficial in acute cases. Work to develop vaccines for human rotavirus has been promising, but a safe vaccine of proven effectiveness is not yet available.


299S1 DGHM Abstracts


title: Clinical, virologic, and serologic evidence of Epstein-Barr virus infection in association with childhood pneumonia()

text: To explore the association of Epstein-Barr virus infection with childhood pneumonia we studied two patients whose mononucleosis-like illnesses were accompanied by pneumonia; both had virologic and serologic evidence of current or recent EBV infection. We then analyzed the sera of 71 children (age range, 14 months to 9 years) with pulmonary infiltrates for the presence of four classes of antibody to EBV. Antibody responses consistent with current or recent EB virus infection were found in 15. Two children had IgM antibodies to the EBV viral antigen at titers ≥1:160, indicating current infection, and all 15 patients had antibody to components of the early antigen complex, suggesting recent infection. A fourfold rise or drop in one or more EBV-specific antibody classes was noted in eight patients within 30 days following onset of clinical illness. Few patients had clinical features suggesting infectious mononucleosis. Eight of the 15 with serologic evidence of current or recent EBV infection also had clinical or serologic evidence of infection with another pathogen-bacterial, viral, or mycoplasmal. Thus, in childhood pneumonia, EBV may be a primary, co-primary, or secondary pathogen; it may be reactivated in the course of infection with another agent, or possibly, by suppressing immune function, it may precipitate infection with some other organism.


title: Colostral transfer of bovine immunoglobulin E and dynamics of serum IgE in calves

text: The role of IgE in protective immunity is becoming understood, therefore the colostral transfer of IgE and the age-dependent changes of IgE levels may be important for neonatal immunity. To investigate this question, serum samples were collected from range-fed Hereford cows and their calves from birth through 9 months of age. The sera were assayed for total IgE by enzyme-linked immunosorbent assay (ELISA). Calves were found to have significant levels of IgE during the first week postpartum, indicating colostral transfer of IgE. Thereafter, serum levels declined rapidly within 3 weeks from birth. The IgE levels began to increase after 12 weeks of age, and in some cases reached adult levels. The passive transfer of maternal IgE through colostrum may be important in providing early protection from disease, especially against intestinal parasites.


title: Viral respiratory diseases in children: Classification, etiology, epidemiology, and risk factors()()()

text: The epidemiology, molecular structure, cell tropism, and pathophysiology of many human disease-causing viruses have been painstakingly and elegantly characterized during the past 50 years. Vaccines and antiviral drugs of varying efficacy were developed and tested. Despite the relegation of smallpox to a freezer chest and the progress in the control of measles and hepatitis B, the viruses that cause respiratory tract infections remain significant causes of illness and death in pediatric populations worldwide. This discussion surveys the virus groups that contain nearly 200 distinct viruses that cause sporadic and epidemic respiratory infections in children. The epidemiology of infection with the influenza A and B, parainfluenza, and respiratory syncytial viruses and adenoviruses and their impact on infants and children and the groups at highest risk for morbid outcomes are discussed. (J PEDIATR 1994;124:S13-S6)


Effective Use of the Diagnostic Laboratory in Dairy Practice


Infectious disease in athletes


title: Multiplex RT-nested PCR differentiation of gill-associated virus (Australia) from yellow head virus (Thailand) of Penaeus monodon

text: A multiplex RT-nested PCR has been developed to detect and differentiate the closely related prawn viruses, gill-associated virus (GAV) from Australia and yellow head virus (YHV) from Thailand. RT-PCR using primers to conserved sequences in the ORF1b gene amplified a 794 bp region of either GAV or YHV. Nested PCR using a conserved sense primer and either a GAV- or YHV-specific antisense primer to a divergent sequence differentially amplified a 277 bp region of the primary PCR amplicon. Multiplexing the YHV antisense primer with a GAV antisense primer to another divergent sequence allowed the viruses to be distinguished in a single nested PCR. Nested PCR enhanced detection sensitivity between 100- and 1000-fold and GAV or YHV RNA was detectable in ∼10 fg lymphoid organ total RNA. The multiplex RT-nested PCR was also able to co-detect GAV and YHV RNA mixed over a wide range of concentrations to simulate potential dual-infection states. The robustness of the test was examined using RNA samples from Penaeus monodon prawns infected either chronically or acutely with GAV or YHV and collected at different locations in Eastern Australia and Thailand between 1994 and 1998. GAV- (406 bp) or YHV-specific (277 bp) amplicons were differentially generated in all cases, including five YHV RNA samples in which no primary RT-PCR amplicon was detected. Sequence analysis of GAV and YHV PCR amplicons identified minor variations in the regions targeted by the virus-specific antisense primers. However, none occurred at positions that critically affected the PCR.


title: Viral proteases as targets for chemotherapeutic intervention

text: Many viruses encode proteinases that are essential for infectivity, and are consequently attractive chemotherapeutic targets. The biochemistry and structure of the human immunodeficiency virus proteinase have been characterized extensively, and potent peptide-mimetic inhibitors have been developed. Techniques and strategies used to improve the efficiency of these compounds are likely to be applicable to other viral proteinases.


Laboratory Diagnosis of Swine Diseases


title: Evidence for the existence of IL-4 and IFNγ secreting cells in the T cell repertoire of naive mice

text: The kinetics with which IgE responses develop in vivo following immunization of experimental animals indirectly support the existence of IL-4-secreting T cells as a normal component of the T cell repertoire. At the same time, studies of IL-4-secreting cell frequencies directly ex vivo have argued that T cells with the potential to become IL-4 secretors exist in vivo, in the form of precursors requiring stimulation and 4 – 12 days of culture as well as restimulation with mitogen or Ag before they become detectable as lymphokine-secreting cells. We demonstrate here that intravenous administration of low doses of anti-CD3 mAb 145-2C11 results in IL-4 production within 60 min of stimulation as demonstrated by Northern analysis of mRNA and a sensitive, selective bioassay (CT.4S cell proliferation) of biologically active IL-4 protein. Production of IL-4 is paralleled by IFNγ synthesis, displaying similar kinetics. These findings, consistent with the presence of mature cells capable of IL-4 and IFNγ synthesis in the T cell repertoire of naive mice, are supported by the observation that stimulation of spleen cells from naive mice with anti-CD3 mAb in vitro for 12 h also results in strong IL-4 and IFNγ mRNA and protein synthesis. The data support and extend those obtained through analysis of cytokine mRNA synthesis alone, thereby providing evidence that “fresh” T cells are indeed capable of producing IL-4 directly ex vivo and are consistent with the existence of IL-4-secreting cells as a normal component of the T cell repertoire of naive mice.


title: Ste24: An Integral Membrane Protein Zinc Metalloprotease with Provocative Structure and Emergent Biology

text: Ste24, an integral membrane protein zinc metalloprotease, is found in every kingdom of eukaryotes. It was discovered approximately 20 years ago by yeast genetic screens identifying it as a factor responsible for processing the yeast mating a-factor pheromone. In animals, Ste24 processes prelamin A, a component of the nuclear lamina; mutations in the human ortholog of Ste24 diminish its activity, giving rise to genetic diseases of accelerated aging (progerias). Additionally, lipodystrophy, acquired from the standard highly active antiretroviral therapy used to treat AIDS patients, likely results from off-target interactions of HIV (aspartyl) protease inhibitor drugs with Ste24. Ste24 possesses a novel “α-barrel” structure, consisting of a ring of seven transmembrane α-helices enclosing a large (> 12,000 Å(3)) interior volume that contains the active-site and substrate-binding region; this “membrane-interior reaction chamber” is unprecedented in integral membrane protein structures. Additionally, the surface of the membrane-interior reaction chamber possesses a strikingly large negative electrostatic surface potential, adding additional “functional mystery.” Recent publications implicate Ste24 as a key factor in several endoplasmic reticulum processes, including the unfolded protein response, a cellular stress response of the endoplasmic reticulum, and removal of misfolded proteins from the translocon. Ste24, with its provocative structure, enigmatic mechanism, and recently emergent new biological roles including “translocon unclogger” and (non-enyzmatic) broad-spectrum viral restriction factor, presents far differently than before 2016, when it was viewed as a “CAAX protease” responsible for cleavage of prenylated (farnesylated or geranylgeranylated) substrates. The emphasis of this review is on Ste24 of the “Post-CAAX-Protease Era.”


title: Design of the first highly potent and selective aminopeptidase N (EC 3.4.11.2) inhibitor

text: A series of phosphinic compounds mimicking the transition state of substrates hydrolysed by aminopeptidase N (EC 3.4.11.2) were synthesized. These new compounds have potent inhibitory activities with Ki values in the nanomolar range. These derivatives behave as the most potent APN inhibitors designed to date.


title: Vγ9Vδ2 T cell-mediated non-cytolytic antiviral mechanisms and their potential for cell-based therapy

text: In healthy adult Homo sapiens, the most frequent circulating γδ T cells (Vγ9Vδ2) respond to pyrophosphomonoesters, alkylamines (together referred to as non-peptidic antigens, NpAgs) and nitrogen-containing bisphosphonates. The seemingly very low toxicity of bisphosphonate and pyrophosphomonoester drugs in vivo, may allow novel approaches to the immunotherapy of viral infections. For example, these drugs can be used to stimulate Vγ9Vδ2 T cells to release antiviral molecules that directly suppress virus replication without destroying the virus-replicating cells. In addition, the soluble molecules released by γδ T cells could boost the antiviral potency of cytotoxic T lymphocytes (CTLs) and promote antigen presentation. The relative therapeutic value of drug-induced direct antiviral and immunoregulatory activities may depend on the infecting virus as well as on the nature of protective immune responses.


OTC product: Kleenex Anti-Viral tissue


An invited commentary on: “Evidence based management guideline for the COVID-19 pandemic - Review article”


Opportunities for rapid viral diagnosis


title: A rapid, quantitative assay for titration of bovine virus diarrhoea-mucosal disease virus()

text: An end point dilution microtitration assay is described that can be used for the titration of both cytopathic and non-cytopathic isolates of bovine virus diarrhoea-mucosal disease virus. Indirect immunofluorescence is used to detect infected MDBK cells in the wells of Terasaki plates. The virus titre is derived from the number of uninfected wells, using the Poisson distribution. The assay is simple, fast and economical. Titres of cytopathic virus determined by the microtitration assay and standard plaque assay are equivalent.


title: Seasonality and prevalence of rotavirus in Al-Ain, United Arab Emirates

text: Background: Rotaviruses are the single most important causative agent of acute neonatal enteritis in most avian and mammalian species including humans. Rotaviruses infections have also been shown to be associated with the elderly, immunocompromised individuals and more recently with epidemic diarrheal illness in adults. Objectives: To study the incidence and the effect of seasonality on the prevalence of rotaviruses in Al-Ain, United Arab Emirates. Study design: A total of 650 stool samples submitted to the laboratories of two University Teaching Hospitals (Al-Ain and Tawam) and a private hospital (Oasis) were examined for the presence of rotaviruses from January 1990–December, 1992, using a commercially available latex agglutination assay. The meteorological data (temperature, relative humidity and rainfall) recorded during the sampling period was analyzed statistically to examine the effect of seasonality on the prevalence of rotavirus cases in Al-Ain, United Arab Emirates. Results: Rotavirus was detected in 21.4% of the samples examined. The predominant number of positive cases (35%) were in the 7–12 months age group. It was interesting to find rotavirus-positive cases in as low an age group as <3 months (3.6%) and as high as 10 years (8.04%). There was no significant difference on infection rates between male and female groups in the study. However, there was a significant difference between the national (38.18%) and non-national children (61.28%). The higher rate of the latter may be due to import of infections. There appeared to be a seasonal pattern of rotavirus occurrence in the cases studied, with a marked increase in the number of positive cases during the months when the relative humidity was low (25–45%) and there was no rainfall. Conclusions: Rotavirus was detected in all age groups with a predominance in 7–12 month age groups, and a higher incidence in non-nationals. There was a marked increase in the number of positive cases during the months when the relative humidity was low (25–45%) and there was no rainfall. These findings are discussed in relation to the epidemiology and prophylaxis of rotavirus infections.


HIV genetic variation: Life at the edge


title: New Developments in Fungal Virology

text: Although viruses are widely distributed in fungi, their biological significance to their hosts is still poorly understood. A large number of fungal viruses are associated with latent infections of their hosts. With the exception of the killer-immune character in the yeasts, smuts, and hypovirulence in the chestnut blight fungus, fungal properties that can specifically be related to virus infection are not well defined. Mycoviruses are not known to have natural vectors; they are transmitted in nature intracellularly by hyphal anastomosis and heterokaryosis, and are disseminated via spores. Because fungi have a potential for plasmogamy and cytoplasmic exchange during extended periods of their life cycles and because they produce many types of propagules (sexual and asexual spores), often in great profusion, mycoviruses have them accessible to highly efficient means for transmission and spread. It is no surprise, therefore, that fungal viruses are not known to have an extracellular phase to their life cycles. Although extracellular transmission of a few fungal viruses have been demonstrated, using fungal protoplasts, the lack of conventional methods for experimental transmission of these viruses have been, and remains, an obstacle to understanding their biology. The recent application of molecular biological approaches to the study of mycoviral dsRNAs and the improvements in DNA-mediated fungal transformation systems, have allowed a clearer understanding of the molecular biology of mycoviruses to emerge. Considerable progress has been made in elucidating the genome organization and expression strategies of the yeast L-A virus and the unencapsidated RNA virus associated with hypovirulence in the chestnut blight fungus. These recent advances in the biochemical and molecular characterization of the genomes of fungal viruses and associated satellite dsRNAs, as they relate to the biological properties of these viruses and to their interactions with their hosts are the focus of this chapter.


title: Reovirus infection in adult mice: the virus hemagglutinin determines the site of intestinal disease

text: Reovirus type 1, strain Lang, and type 3, strain Dearing, induced site-specific intestinal lesions in the adult mouse after intravenous inoculation. Reovirus type 1 caused inflammation and epithelial changes such as loss of nuclear polarity, villus blunting and crypt hyperplasia restricted to the ileum. In contrast, reovirus type 3 induced duodenitis, jejunitis, and ulcerative colitis. In the duodenum and jejunum, the epithelial cells appeared normal, but hemorrhage and inflammation in the lamina propria was present. In the colon, superficial ulceration, crypt abscesses, and intraluminal hemorrhage was observed. Segregation analysis using reassorant clones derived from reoviruses 1 and 3, suggested the viral hemagglutinin, encoded by genome segment S1, to be the major viral determinant of site specific intestinal disease following intravenous inoculation.


Amantadine for chronic hepatitis C: a magic bullet or yet another dead duck?


title: [32] Families of cysteine peptidases

text: This chapter presents families of cysteine peptidases. The activity of all cysteine peptidases depends on a catalytic dyad of cysteine and histidine. The order of the cysteine and histidine residues (Cys/His or His/Cys) in the linear sequence differs between families and this is among the lines of evidence suggesting that cysteine peptidases have had many separate evolutionary origins. The families C1, C2, and C10 can be described as “papainlike,” and form clan CA. The papain family contains peptidases with a wide variety of activities, including endopeptidases with broad specificity, endopeptidases with narrow specificity, aminopeptidases, and peptidases with both endopeptidase and exopeptidase activities. Papain homologs are generally either lysosomal or secreted proteins. The calpain family includes the calcium-dependent cytosolic endopeptidase calpain, which is known from birds and mammals, and the product of the sol gene in Drosophila. Calpain is a complex of two peptide chains. Picornains are a family of polyprotein-processing endopeptidases from single-stranded RNA viruses. Each picornavirus has two picornains (2A and 3C).


Improved cutaneous genetic immunization by microneedle array delivery of an adjuvanted adenovirus vaccine


Clinically distinguishable syndromes caused by viruses


title: Ribavirin efficacy in an in vivo model of Crimean-Congo hemorrhagic fever virus (CCHF) infection()

text: After intraperitoneal (i.p.) infection of infant mice with CCHF virus, virus titers in liver remained significantly higher than in other organs except blood (serum). Within the liver, virus antigen was first found by immunofluorescence (IFA) in Kupffer cells followed by more extensive hepatic spread. Later, virus was found in other organs including brain and heart. Ribavirin treatment significantly reduced infant mouse mortality and extended the geometric mean time to death. Ribavirin treatment reduced CCHF virus growth in liver and significantly decreased, but did not prevent, viremia. Despite a substantial viremia, infection of other organs including brain and heart was not detected in ribavirin-treated mice. A hepatotropic virus subpopulation with less neurovirulence than the parent was isolated from liver of ribavirin-treated mice (single dose, 100 mg/kg). After serial passage in placebo-treated mice, the exclusive hepatotropism was lost.


Virus-induced autoimmunity: Molecular mimicry as a route to autoimmune disease


title: Improvements in obtaining and characterizing mouse cerebrospinal fluid(): Application to mouse hepatitis virus-induced encephalomyelitis

text: This report describes advances in techniques for analyzing cellular and humoral immune components in the cerebrospinal fluid (CSF) of the mouse that are applicable to other laboratory animals. CSF studies undertaken during experimental infection of mice with JHM strain virus (JHMV) of mouse hepatitis virus are presented. A critical pitfall which can lead to erroneous or invalid results is contamination of the CSF by even minute quantities of blood. Means of avoiding this contamination are attention to anatomical reference points, the use of a micropipet, and prior intracardiac perfusion of animals with phosphate-buffered saline. Cells in the CSF were typed as either B, T, polymorphonuclear, or mononuclear cells by the combination of a microcytotoxicity assay and histologic stains. A radioimmunoassay (RIA) allowed quantification of antibodies to JHMV in the CSF and indicated the presence of intrathecal synthesis of antibody in chronically infected mice. The combined use of these sensitive methods makes possible CSF analysis in individual mice rather than in pooled groups.


title: Does muscle activation occur by direct mechanical coupling of transverse tubules to sarcoplasmic reticulum?

text: Our knowledge of the physiological and biochemical constituents of skeletal muscle excitation has increased greatly during the last few years but this has not led to a consensus of the physiological mode of muscle activation. Three hypotheses of transmission, involving either transmitter-receptor interaction or direct mechanical coupling, are still under active consideration. The hypothesis of direct mechanical coupling currently being evaluated proposes that the dihydropyridine receptor in the transverse tubules serves as a voltage sensor that communicates directly with the junctional foot protein/Ca(2+) channel of sarcoplasmic reticulum to initiate opening of the channel.


The spectrum of severe wheezing in childhood()


title: Chapter 8 Paramyxoviruses

text: The paramyxoviruses are a heterogeneous group of viruses causing a variety of clinical diseases in humans, animals, and birds. This chapter examines in more detail the structure and properties of the important human viruses in this group, namely measles, respiratory syncytial virus (RSV), mumps and parainfluenza viruses I-V. They are all enveloped, negative-stranded, riboviruses of helical symmetry. It is suggested that susceptible children, adolescents, and adults should be vaccinated against mumps, unless vaccination is contraindicated. Mumps vaccine can be of particular value to children approaching puberty and for adolescents and adults, especially males who have not had mumps in childhood. Ribavirin therapy may be particularly beneficial for children at risk for severe and often fatal RSV infection, such as infants with congenital heart disease. Attenuated measles vaccines have been developed empirically by selection of host range mutants, and are widely and successfully used throughout the world. Using the vaccine, some countries may soon eliminate measles as an endogenous virus but continued problems are anticipated, particularly in adults with viruses re-introduced by visitors from abroad. Basic studies on new antivirals are continuing (particularly with oligopeptides) but antiviral compounds are unlikely to have extended use in the clinic, except perhaps in tropical areas where the disease may be life threatening. However, a vaccination programme in these areas is preferable, and is an urgent need.


title: Crossed immunoelectrophoresis: Qualitative and quantitative considerations

text: Invented 20 years ago, crossed immunoelectrophoresis (X-IEP) today is a technique of unusual power and myriad application. It combines very high resolution with exquisite specificity by alloying 2-dimensional electrophoresis with immunoprecipitation for symbiotic new potentialities. The consequent matchless quantitative/qualitative capabilities of X-IEP for analyzing antigens in complex mixtures, particularly by their idiomatic internal comparisons, are still not widely recognized. Because of this and the supposed complications of its use and interpretation, X-IEP is more rarely used than it should be. This essay discusses contemporary X-IEP with the particular aims of demonstrating that it is not difficult to use and of explaining with selected examples why it is peculiarly powerful for analyzing antigen mixtures like the body fluids, tissue and cell extracts, and microbial homogenates.


title: Greater frequency of viral respiratory infections in asthmatic children as compared with their nonasthmatic siblings()

text: A longitudinal clinical and microbiologic surveillance was conducted from October to May, 1971–1972, on 16 children with infectious asthma and 15 of their nonasthmatic siblings. Asthmaticchildren experienced a significantly greater frequency of viral respiratory infections than did nonasthmatic ones (5.1 vs. 3.8 per subject). This increased incidence appeared to be largely the result of a greater number of rhinovirus infections. While respiratory infections of identical etiology that occurred concurrently in an asthmatic and his sibling were equivalent in severity, illnesses were longer (but not significantly so) in asthmatic children.


Master author index


title: Expression in Escherichia coli and purification of biologically active L proteinase of foot-and-mouth disease virus

text: The foot-and-mouth disease virus (FMDV) Lb gene was cloned into bacterial expression vectors under the control of a T7 RNA polymerase promoter. The Lb protein was expressed in both an in vitro transcription-translation system and in Escherichia coli. In vitro expression of a construct containing the Lb gene fused to a portion of the VP4 and 3D genes demonstrated cis cleavage activity that could be blocked by the thiol protease inhibitor E-64. Lb expressed in E. coli was purified from the soluble fraction by metal chelation chromatography. Purified Lb had trans cleavage activity at the L/P1 junction and cleaved the p220 component of the cap-binding protein complex.


VIRUSES AND GASTROENTERITIS


title: Respiratory illness caused by picornavirus infection: a review of clinical outcomes

text: Background: Respiratory infections result from invasion of the respiratory tract, mainly by viruses, and are the leading cause of acute morbidity in individuals of all ages worldwide. During peak season, picornaviruses cause 82% of all episodes of acute nasopharyngitis (the common cold), the most frequent manifestation of acute respiratory infection, and produce more restriction of activity and physician consultations annually than any other viral or bacterial source of respiratory illness. Objective: This article reviews the clinical impact and outcomes of picornavirus-induced respiratory infections in specific populations at risk for complications. It also discusses the potential economic impact of the morbidity associated with picornavirus-induced respiratory infection. Methods: Relevant literature was identified through searches of MEDLINE, OVID, International Pharmaceutical Abstracts, and Lexis-Nexis. The search terms used were picornavirus, rhinovirus, enterovirus, viral respiratory infection, upper respiratory infection, disease burden, economic, cost, complications, asthma, COPD, immunocompromised, elderly, otitis media, and sinusitis. Additional publications were identified from the reference lists of the retrieved articles. Conclusions: Based on the clinical literature, picornavirus infections are associated with severe morbidity as well as considerable economic and societal costs. Future research should focus on identifying patterns of illness and the costs associated with management of these infections. New treatments should be assessed not only in terms of their ability to produce the desired clinical outcome, but also in terms of their ability to reduce the burden of disease, decrease health care costs, and improve productivity.


title: [33] Using confocal microscopy to study virus binding and entry into cells

text: The chapter presents a discussion on the study of virus binding and entry into cells by using confocal microscopy. For the study new approaches to study vaccinia virus (VV), binding and entry based on confocal microscopy are developed. These techniques do not require virus purification or labeling and generate data that reveal the absolute numbers of virus particles that have bound to or have entered into individual cells. The chapter describes these techniques and then illustrates with some of the results obtained. These methods should be applicable to any virus larger than 50 nm. The chapter discusses the way these techniques have generated data that cannot be obtained with classical binding or entry assays. Vaccina virus is the prototype of the poxvirus family. These are DNA viruses that replicate in the cell cytoplasm and have genomes between 150 and 300 kbp. These techniques are presented with a study of the binding and entry of VV. The methods have been particularly useful for studying VV because this virus produces two different forms of infectious virion that are antigenically and biologically distinct and are produced in widely differing amounts. Moreover, the extracellular enveloped virus (EEV) form of VV cannot be purified from contaminating IMV without disrupting the integrity of the outer envelope.


Nonculturable agents of viral gastroenteritis


title: Regulation of Tobamovirus Gene Expression

text: This chapter discusses tobacco mosaic virus (TMV) strains U1, OM, L, CGMMV, 0, and Cc. The production of each TMV protein is regulated differently, both in amounts and times of production. The chapter discusses some of the strategies that tobamoviruses uses to control gene expression: (1) different subgenomic RNA promoter/leader sequences control timing of expression of genes, (2) genes expressed via subgenomic mRNAs are expressed in decreasing amounts with increasing distances from the 3' terminus, and (3) TMV mRNAs appear to be translationally regulated differently from host mRNAs. Genome organization affects gene expression, but it appears to be equally important for the efficiency of replication and the ability of the genomic structure to be stably propagated. Different virus groups have evolved different gene arrangements. Tobamovirus genes expressed via subgenomic mRNAs appear to be expressed in increasing amounts when positioned nearer the 3’ terminus.


Antiviral agents against respiratory viruses


title: Outcomes of Three- Versus Six-Monthly Dispensing of Antiretroviral Treatment (ART) for Stable HIV Patients in Community ART Refill Groups: A Cluster-Randomized Trial in Zimbabwe

text: INTRODUCTION: Multimonth dispensing (MMD) of antiretroviral treatment (ART) aims to reduce patient-related barriers to access long-term treatment and improve health system efficiency. However, randomized evidence of its clinical effectiveness is lacking. We compared MMD within community ART refill groups (CARGs) vs. standard-of-care facility-based ART delivery in Zimbabwe. METHODS: A three-arm, cluster-randomized, pragmatic noninferiority trial was performed. Thirty health care facilities and associated CARGs were allocated to either ART collected three-monthly at facility (3MF, control); ART delivered three-monthly in CARGs (3MC); or ART delivered six-monthly in CARGs (6MC). Stable adults receiving ART ≥six months with baseline viral load (VL) <1000 copies/ml were eligible. Retention in ART care (primary outcome) and viral suppression (VS) 12 months after enrollment were compared, using regression models specified for clustering (ClinicalTrials.gov: NCT03238846). RESULTS: 4800 participants were recruited, 1919, 1335, and 1546 in arms 3MF, 3MC, and 6MC, respectively. For retention, the prespecified noninferiority limit (-3.25%, risk difference [RD]) was met for comparisons between all arms, 3MC (94.8%) vs. 3MF (93.0%), adjusted RD = 1.1% (95% CI: -0.5% to 2.8%); 6MC (95.5%) vs. 3MF: aRD = 1.2% (95% CI: -1.0% to 3.6%); and 6MC vs. 3MC: aRD = 0.1% (95% CI: -2.4% to 2.6%). VL completion at 12 months was 49%, 45%, and 8% in 3MF, 3MC, and 6MC, respectively. VS in 3MC (99.7%) was high and not different to 3MF (99.1%), relative risk = 1.0 (95% CI: 1.0-1.0). VS was marginally reduced in 6MC (92.9%) vs. 3MF, relative risk = 0.9 (95% CI: 0.9-1.0). CONCLUSION: Retention in CARGs receiving three- and six-monthly MMD was noninferior versus standard-of-care facility-based ART delivery. VS in 3MC was high. VS in six-monthly CARGs requires further evaluation.


title: Correlation of urine pH with the detection of cytomegalovirus by the shell vial technique

text: The influence of the pH of urine on the detection of cytomegalovirus (CMV) by the shell vial assay was evaluated. The pH values of 295 urine specimens ranged from 4.7 to 8.5 (mean 6.3) and were not significantly different in culture-positive versus culture-negative samples. None of the urine specimens appeared to be toxic for the cells used in the shell vial assay. We recommend inoculation of urine specimens into shell vials without adjustment of pH.


title: Viral infections and recurrences of febrile convulsions()

text: To determine whether complicated febrile seizures occur more often in children with a proven viral infection, we performed viral examinations on 144 children with febrile convulsions, of whom 112 had simple and 32 had complicated seizures. A diagnosis of virus infection was verified in 46% of the former patients and 53% of the latter. Three adenoviruses, one parainfluenza virus type 2 and one type 3, one respiratory syncytial virus, one echovirus type 11, one herpes simplex virus type 2, and one influenza B virus were isolated from the cerebrospinal fluid. A simple febrile convulsion occurred in seven children with a positive cerebrospinal fluid viral isolation, and two had a complex febrile seizure. In a follow-up of 2 to 4 years (mean 3.3 years), 21 of the 107 children with simple seizures (19.6%) and 3 of the 32 children with complicated seizures (9.4%) had recurrent febrile seizures. The children with positive evidence for a viral infection, even with a virus isolated from the cerebrospinal fluid, had no more recurrences than those without any proven viral infection. We conclude that children with a proven viral infection have no worse prognosis than those without.


Expanded Telehealth Services Offer Smart Wound Care Workflows


O14 Has the 7-valent pneumococcal conjugate vaccine (PCV7) reduced hospital visits and admissions for pneumonia in young children in Calgary?


Avian flu virus H5N1: No proof for existence, pathogenicity, or pandemic potential; non-“H5N1” causation omitted


title: The Morphology of Virus-Antibody Interaction

text: In the field of virus study, the electron microscope technique of negative staining is now more than 10 years old, and during these years the knowledge of virus fine structure has changed beyond all recognition. This chapter describes that the immune aggregate should be incubated for 1 hour at 37°C and then left in the cold overnight. This is the optimum approach for a system, where the concentration of neither the antigen nor the antiserum is known, and maximum clumping is needed. However, with many systems these parameters have been established, and if it is known that clumping can be obtained readily, for example, as with the avian infectious bronchitis system, then incubation for 1 hour at 37°C is sufficient, followed by spinning at 10,000 rpm for half an hour. Viruses in the small to intermediate size range are ideal for immune studies, as the particles are not disproportionately larger than the antibody molecules attached to them, and interaction between them can be visualized with better than 10 a resolution. Particles as large as the poxviruses are becoming too large for good resolution of antibody molecules to be obtained, and aggregates of poxvirus particles are usually too dense to be recorded photographically except at low power. In the field of clinical virology, there is a possibility that the electron microscope technique of negative staining will become a standard method of diagnosis. As far as research is concerned, the present article seems to have described the beginnings that have been made in the visualization of several aspects of antigen-antibody interaction. Each line investigated has yielded a few answers, but of much greater importance, has led to a better understanding of what questions should be asked. At present, viral antigens can only occasionally be obtained in pure form, such that there are only a very few systems where controlled and specific virus-antigen-antibody systems can be visualized.


title: Tailed Bacteriophages: The Order Caudovirales

text: This chapter discusses the common properties of tailed phages and potential criteria for their classification as an order and situating tailed phages with respect to other viruses. Tailed bacteriophages have a common origin and constitute an order with three families, named Caudovirales. Their structured tail is unique. Tailed phages share a series of high-level taxonomic properties and show many facultative features that are unique or rare in viruses—for example, tail appendages and unusual bases. They share with other viruses, especially herpesviruses, elements of morphogenesis and lifestyle that are attributed to convergent evolution. Tailed phages present three types of lysogeny, exemplified by phages λ, Mu, and P1. Lysogeny appears as a secondary property acquired by horizontal gene transfer. Amino acid sequence alignments (notably of DNA polymerases, integrases, and peptidoglycan hydrolases) indicate frequent events of horizontal gene transfer in tailed phages. Common capsid and tail proteins have not been detected. Present-day tailed phages appear as chimeras, but their monophyletic origin is still inscribed in their morphology, genome structure, and replication strategy. It may also be evident in the three-dimensional structure of capsid and tail proteins. It is unlikely to be found in amino acid sequences because constitutive proteins must be so old that relationships were obliterated and most or all replication-, lysogeny-, and lysis-related proteins appear to have been borrowed.


title: Phosphorylation of the mouse hepatitis virus nucleocapsid protein

text: Analysis of the radiolabeled tryptic peptides derived from the nucleocapsid proteins of two serotypes of mouse hepatitis virus showed each to have a small number of unique peptides; however, twobiologically distinct variants of the JHM strain appeared identical. Analysis of [(32)P]-labeled nucleocapsid-derived peptides showed that phosphorylation occurs at only a few sites and that all three viruses differed in the sites of phosphorylation. No differences in the sites of phosphorylation were found between the nucleocapsid proteins derived from purified virions and the membranes or the cytosol of infected cells, suggesting that post-translational phosphorylation plays no role in the regulation of viral assembly. These data show unequivocal evidence that the nucleocapsid proteins of mouse hepatitis virus strains differ in the sites of phosphorylation.


title: Biological studies of the fusion function of California serogroup Bunyaviruses

text: Like other enveloped viruses, La Crosse virus is capable of inducing membrane fusion after exposure to mild acid. This function is known to have biological significance at the level of the whole organism, since it has been related to infection in a mouse model. In this report the process of fusion-from-within (FFWI) for LAC and other members of the California serogroup of Bunyaviruses is characterized. Like fusion-from-without, FFWI is dependent on pH, temperature, and number of virus particles present in the supernatant of fusing cells. Electron micrographs demonstrate that LAC mediated cell membrane fusion is a rapid, multi-point event, and that other than fusion of their plasma membranes, the cells do not show any morphological change. In agreement with theory, lysosomotropic agents were capable of inhibiting La Crosse virus infection. This inhibition was not due to non-specific toxic effects on infected cells. Finally, fusion studies of other California serogroup members revealed minor differences in the pH of fusion induction in some strains. These differences were consistent with the known subtyping within the serogroup.


Determining Urgent/Emergent Status of Gastrointestinal Endoscopic Procedures in an Ambulatory Care Setting During the COVID-19 Pandemic: Additional Factors That Need To Be Considered


title: An ELISA system for evaluating antiretroviral activity against Rauscher murine leukemia virus

text: A system for evaluating the activity of antiviral agents against Rauscher murine leukemia virus (R-MuLV) has been developed using an enzyme linked immunosorbent assay technique. The activity of various antiviral compounds demonstrated in this assay system has been compared to their activity in the UV-XC plaque reduction assay, which has been used historically for evaluating anti-R-MuLV compounds. The assay is based upon detection of R-MuLV encoded p30 protein production in virus infected murine cells. The assay reagents are readily available and the assay system is amenable to automated data collection systems. Cytotoxicity evaluations are conducted in parallel to the Rauscher MuLV ELISA assay in order to assess drug-induced reductions in cell viability. Cytotoxicity evaluations are important to interpretation of the ELISA results since reductions in cell viability reduce viral protein production which would indicate an antiviral drug effect. This system is less sensitive than the classical UV-XC plaque reduction assay; however, it does offer an alternative to the time-consuming and labor-intensive plaque assay.


title: Antibody-Mediated Destruction of Virus-Infected Cells

text: This chapter describes the effect of antibody on virus-infected cells with special reference to the human system. The destruction by antibody of the infected cells through the mediation of complement is described in detail based in considerable part on the contributions of the authors. Activation of the alternative pathway by the various infected cells is of special interest. The interesting effect of the antibody-dependent cell-mediated cytotoxicity (ADCC) system involving viral antigens in cell killing is also presented. Multiple additional topics are also covered, such as the effect of antibody on the expression of viral proteins both on the surface of the cell and intracellularly. Serum antibody, produced in response to virus infections, is of major importance in preventing the spread of infection by virtue of neutralizing free virus in extracellular fluids. Virus neutralization by antibody is enhanced by complement. Antibody binding to the surface of virus-infected cells can affect virus production and release in the absence of an effector system. Immunoglobulin (IgG) antibody can mediate the destruction of virus-infected cells in conjunction with complement or cytotoxic lymphocytes. In addition, at a conceptual level there is evidence to suggest that antibody may enhance and confer specificity on basic nonspecific humoral and cell-mediated defense mechanisms.


Human bocavirus 1 may suppress rhinovirus-associated immune response in wheezing children


title: Modulation of MHC antigen expression by viruses and oncogenes

text: It is becoming increasingly clear that regulation of MHC antigen expression by viruses and oncogenes, leading to either immune evasion or autoimmunity, is widespread and important in disease. At a recent meeting, which brought together workers interested in tumour immunology, viral infection and the MHC, a number of mechanisms for the regulation of MHC antigen expression were revealed and the importance of balanced expression of MHC gene products to effective immunity was underlined.


title: The potential use of liposome-mediated antiviral therapy

text: The natural targeting of liposomes to cells of the reticuloendothelial system should be exploited to examine whether selective delivery of antiviral or immunomodulatory agents could be beneficial for the treatment of viral diseases. In this review we discuss the potential use of liposomes in the treatment of virus diseases, the targeting of liposome-encapsulated immunomodulators to macrophages in order to render these cells cytolytic for virus-infected cells, and the targeting of liposome-encapsulated antiviral drugs to macrophages to achieve direct suppression of virus replication within these cells.


title: Muramyl peptides confer hepatoprotection against murine viral hepatitis

text: The hepatoprotection induced by synthetic muramyl peptides was investigated using a model of lethal murine mouse hepatitis MHV-3 virus infection. MDP and a nonpyrogenic analog, Murametide, inhibited the steep elevation of serum transaminases induced by MHV-3 irrespective of whether the immunomodulators were administered before or after the infection. A significant proportion of MDP or Murametide-treated animals, in contrast to controls, survived the MHV-3 infection. The histopathological examination of the liver revealed marked necrosis of the hepatic parenchymal cells and infiltration of the inflammatory cells in controls but not in MDP-treated animals.


title: Complex Carbohydrates in Drug Development

text: Recent advances in carbohydrate chemistry and biochemistry afford the opportunity to develop bioactive complex carbohydrates, per se, as drugs or as lead compounds in drug development. Complex carbohydrates are unique among biopolymers in their inherent potential to generate diverse molecular structures. While proteins vary only in the linear sequence of their monomer constituents, individual monosaccharides can combine at any of several sites on each carbohydrate ring, in linear or branched arrays, and with varied stereochemistry at each linkage bond. This chapter addresses some salient features of mammalian glycoconjugate structure and biosynthesis, and presents examples of the biological activities of complex carbohydrates. The chapter presents selected examples that will provide an accurate introduction to their pharmacological potential. In addition to their independent functions, oligosaccharides can modify the activities of proteins to which they are covalently attached. Many glycoprotein enzymes and hormones require glycosylation for expression and function. The chapter discusses the ancillary role of carbohydrates that is of great importance to the use of engineered glycoproteins as pharmaceuticals.


title: Increased susceptibility of aged rats to haemorrhage and intravascular hypercoagulation following endotoxin administered in a generalized Shwartzman regime

text: Ageing rats are known to have an increased incidence of myocardial fibrosis and dyspnoea caused by pulmonary intravascular coagulation. In order to determine whether endotoxin can be responsible for such responses in ageing rats we have exposed rats of differing ages (2 months, 16 months and 24 months) to single or repeated (two doses 24 h apart; generalized Shwartzman regime) intravenous doses of endotoxin (E. coli 0111134). Only the 2-year-old rats reacted adversely. Two doses of endotoxin produced death, with focal myocardial necrosis, haemorrhage and pulmonary and hepatic intravascular coagulation. The increased susceptibility of aged rats to the toxic effects of endotoxin explains some of the changes found in the tissues of old rats. The sporadic nature of both cardiac failure and dyspnoea as a cause of morbidity and mortality in ageing rats may be related to the need for two endotoxin episodes in a period of 24 h to provoke a generalized Shwartzman reaction, an occurrence likely to be relatively uncommon under natural conditions.


title: ASYMPTOMATIC ENDEMIC ROTAVIRUS INFECTIONS IN THE NEWBORN

text: Between May 1, 1976, and May 14, 1977, 343 (32·5%) of 1056 5-day-old babies in newborn nurseries excreted rotaviruses. The infection-rate was highest during winter (49%). 76% of infected babies at this time were bottle-fed. 41% of neonates excreted low amounts of virus (10(8) particles/g fæces); older children tended to excrete >10(10) particles/g fæces. Infected breast-fed babies excreted less virus than those who were bottle-fed. Stools of breast-fed babies often contained clumps of complete "smooth" rotavirus particles. When the newborn nurseries were transferred to a newly built hospital wing, infection appeared in the new wards, including those admitting only new patients, within a short period. Infection was either mild (8%) or symptomless (92%), and even babies with symptoms required no treatment.


title: Semliki Forest Virus: A Probe for Membrane Traffic in the Animal Cell

text: The traffic among the cellular compartments is thought to be mediated by membrane vesicles, which bud from one compartment and fuse with the next. Despite the continuous exchange of membrane components among them, the organelles maintain their characteristic protein and lipid compositions such that the traffic remains selective, thus, avoiding intermixing of components. This membrane traffic recycles components from the cell surface to the interior of the cell and back to the cell surface again. The membrane traffic between the ER and the cell surface involves a major sorting problem. Little is known of how the animal cell has solved this problem in molecular terms. One experimental tool in this direction is provided by some enveloped animal viruses, which mature at the cell surface of infected cells. Such viruses include influenza virus, Semliki Forest virus (SFV), Sindbis virus, and vesicular stomatitis virus (VSV). They are extremely simple in makeup and hence are very well characterized. The purpose of this article is to illustrate the use of the enveloped viruses as tools in the study of membrane traffic in the animal cell. This is done in the context of the life cycle of the virus in the host cell. The article will be concerned mainly with Semliki Forest virus (SFV), which is the virus that has been worked upon in the chapter. SFV belongs to the alphaviruses, a genus of the togavirus family.


title: DIAGNOSIS AND MANAGEMENT OF RHINITIS

text: The complaint of rhinitis is one of the most frequent reasons why patients seek a physician's evaluation. Rhinitis is an inflammatory response of the nasal mucosa to various stimuli (both allergic or nonallergic). It is characterized by symptoms of nasal congestion, sneezing, nasal pruritis, and rhinorrhea.(49) The prevalence of rhinitis and the economic impact for both patient and managed care organizations dictate that clinicians carefully consider the medications available to them.


title: Recent Developments in Viral Gastroenteritis

text: In recent years impressive advances have been made in understanding viral gastroenteritis. A specific causative agent has been identified in infants and young children, and studies of a similar but distinct enteritis in piglets have given new insight into the pathogenesis of viral diarrhea. This article discusses these recent findings in veterinary and human medicine.


title: CLINICAL VIRAL INFECTIONS AND MULTIPLE SCLEROSIS

text: Over an 8 year period, 170 patients with multiple sclerosis (MS) and 134 healthy controls were assessed at monthly intervals in order to ascertain environmental factors which might be important in producing exacerbation or progression of the illness, and to compare the frequency of common viral infections in the two groups. During cumulative periods designated "at risk" (2 weeks before the onset of infection until 5 weeks afterwards) annual exacerbation rates were almost 3-fold greater than those during periods not at risk. Approximately 9% of infections were temporally related to exacerbations, whereas 27% of exacerbations were related to infections. Frequency of common infections was approximately 20-50% less in MS patients than controls; it was progressively less in those with greater disability. Even in minimally disabled patients with similar potential for infectious contacts, the infection rate was significantly less than in controls, suggesting that MS patients could have superior immune defences against common viruses.


title: The blind watchmaker and rational protein engineering

text: In the present review some scientific areas of key importance for protein engineering are discussed, such as problems involved in deducting protein sequence from DNA sequence (due to posttranscriptional editing, splicing and posttranslational modifications), modelling of protein structures by homology, NMR of large proteins (including probing the molecular surface with relaxation agents), simulation of protein structures by molecular dynamics and simulation of electrostatic effects in proteins (including pH-dependent effects). It is argued that all of these areas could be of key importance in most protein engineering projects, because they give access to increased and often unique information. In the last part of the review some potential areas for future applications of protein engineering approaches are discussed, such as non-conventional media, de novo design and nanotechnology.


Early coagulopathy in severe iron poisoning


title: WHAT CLINICIANS NEED TO KNOW ABOUT ANTIVIRAL DRUGS AND VIRAL RESISTANCE

text: During the last decade, significant advances have been made in the development and use of antiviral agents for the successful treatment of a number of viral infections.8, 51, 57 An expanding array of antiviral drugs are currently available for the management of infections caused by herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), cytomegalovirus (CMV), varicella-zoster virus (VZV), influenza A virus, respiratory syncytial virus (RSV), human immunodeficiency virus type 1 (HIV-1), papillomaviruses, and hepatitis B and C viruses. The increased number and use of antiviral agents, however, has led to the emergence of drug-resistant viruses, particularly in immunocompromised patients such as those with acquired immunodeficiency syndrome (AIDS) or hematologic malignancy or those who have undergone organ transplantation. For comprehensive reviews on specific viruses, see references 26, 41, 64, 81–83, and 102. Clinical situations that favor the development of resistance include long-term suppressive therapy, recurrent intermittent therapy, and the use of less than optimum doses of an antiviral agent. Generally, the emergence and isolation of drug-resistant viruses is associated more so with the therapeutic use of antiviral agents and does not seem to be caused by prophylactic treatment. As more patients fail to respond to appropriate therapy and additional antiviral agents are produced, it will also become important for diagnostic virology laboratories to provide rapid and practical antiviral susceptibility testing to assist physicians in defining drug resistance and choosing appropriate alternative therapies. This review describes the major antiviral agents, their mechanisms of action, and the development of drug resistance following antiviral therapy. A brief overview of the available phenotypic and genotypic susceptibility assays for detecting antiviral resistance is also discussed.


title: The Molecular Biology of Influenza Virus Pathogenicity

text: It is an accepted concept that the pathogenicity of a virus is of polygenic nature. Because of their segmented genome, influenza viruses provide a suitable system to prove this concept. The studies employing virus mutants and reassortants have indicated that the pathogenicity depends on the functional integrity of each gene and on a gene constellation optimal for the infection of a given host. As a consequence, virtually every gene product of influenza virus has been reported to contribute to pathogenicity, but evidence is steadily growing that a key role has to be assigned to hemagglutinin. As the initiator of infection, hemagglutinin has a double function: (1) promotion of adsorption of the virus to the cell surface, and (2) penetration of the viral genome through a fusion process among viral and cellular membranes. Adsorption is based on the binding to neuraminic acid-containing receptors, and different virus strains display a distinct preference for specific oligosaccharides. Fusion capacity depends on proteolytic cleavage by host proteases, and variations in amino acid sequence at the cleavage site determine whether hemagglutinin is activated in a given cell. Differences in cleavability and presumably also in receptor specificity are important determinants for host tropism, spread of infection, and pathogenicity. The concept that proteolytic activation is a determinant for pathogenicity was originally derived from studies on avian influenza viruses, but there is now evidence that it may also be relevant for the disease in humans because bacterial proteases have been found to promote the development of influenza pneumonia in mammals.


title: Mouse hepatitis virus infection of mice causes long-term depletion of lactate dehydrogenase-elevating virus-permissive macrophages and T lymphocyte alterations

text: Intraperitoneal injection of pathogen-free B10.A mice with mouse hepatitis virus (MHV)-A59 resulted in a short subclinical infection which was terminated by a rapid antiviral immune response. The infection resulted in a rapid, but transient, about 10-fold increase in the number of macrophages and total cells in the peritoneum of the mice. This increase was preceded by a complete depletion of the peritoneum of the subpopulation of macrophages that supports a productive infection by lactate dehydrogenase-elevating virus (LDV). The depletion of LDV-permissive macrophages was a long-term effect; at 50 days post-infection with MHV, the proportion of LDV-permissive macrophages in the peritoneum had reached only 20% of that observed in the peritoneum of uninfected mice, whereas the total number of macrophages in the peritoneum had returned to normal. Furthermore, MHV infection resulted in a long-term alteration in the proliferative response of spleen T cells to concanavalin A (ConA) and in their ability to produce interferon γ; several times higher concentrations of ConA were required to induce a maximum proliferative response in spleen T cell populations from 5-week MHV-infected B10.A mice than in spleen T cell populations from infected companion mice but the former produced 5 times more interferon γ than the T cells from unifected mice.


Inflammation: Patterns and new concepts


Ethical aspects of vaccines and vaccination


title: Microbial nomenclature: A list of names and origins

text: Microbial nomenclature underwent a large number of changes in the 1970s. Many species of pathogens were added and many others experienced name changes. These modifications primarily were due to two unrelated factors: the use of new DNA hybridization techniques and the advent of computerized literature searches to establish historical precedence. In 1980 an approved list of microbial names was published. This list fixed and legitimized bacterial nomenclature. All future additions or alterations to it had to pass international scientific committees. This list has now been accepted by the scientific community. The derivation of these names are presented in this review.


title: Viral Pathogens of the Penaeid Shrimp

text: While significant advances that have been made in determining the role of viruses involved in various epizootics occurring in penned shrimp aquaculture, viral diseases will continue to plague the industry. A major obstacle to the study of these diseases is the lack of convenient and quantitative methodologies, such as in vitro cell culture systems to grow and study (characterize) the virus. A beginning has been made with the recent development of protocols for the consistent preparation of primary shrimp lymphoid cells, which were employed for the quanta1 assay of some of the shrimp viral pathogens. The primary cell lines have also been used to analyze the synthesis of viral proteins at the cellular level and to study viral pathogenesis. With the further successful development of additional primary cell lines from other shrimp tissues and the establishment of continuous diploid and transformed shrimp cell lines, this problem is being solved. The value of cell culture systems is becoming increasingly clear. They present several obvious advantages because (1) they are more cost effective, sensitive, and convenient than whole animals, particularly for rapid monitoring of infectivity, (2) they yield quantitatively reproducible results, and (3) viral growth kinetics, biochemical and genetic characteristics, and so on can be studied more easily. Their biggest potential use is in future molecular biology and genetic studies of shrimp viruses.


title: AN ENVELOPED VIRUS IN STOOLS OF CHILDREN AND ADULTS WITH GASTROENTERITIS THAT RESEMBLES THE BREDA VIRUS OF CALVES

text: Pleomorphic virus-like particles about 100 nm in diameter with a fringe of closely applied peplomers (7-9 nm in length) were observed by electron microscopy in the stools of 20 children and adults with gastroenteritis. In most of the samples no other viral or bacterial pathogens were detected. In form and under immune electron microscopy these virus-like particles resembled the Breda virus isolated from diarrhoeic calves. These objects may be a viral pathogen of humans.


The microbiology associated with cystic fibrosis


Summary of the II international consensus symposium on combined antiviral therapy and implications for future therapies


title: Persistent Viral Infections as Models for Research in Virus Chemotherapy

text: The acute systemic virus infection is commonly used as an experimental model in chemotherapy research despite the fact that the chance for an effective chemotherapy of acute virus infections is small. In most acute infections, virus multiplication is well advanced before the disease is expressed and treatment will, in many cases, come too late. However, control by chemotherapy might be promising for persistent virus infections, where, owing to the slow progression of the disease, sufficient time for treatment is available. Although there are various ways in which viruses can persist in their hosts, comparative studies in vitro and in vivo reveal common features that shall be briefly reviewed. Animal models with persistent virus infections are usually difficult to experiment with because of the varying length of the incubation period brought about by the complex relationship among virus replication, immune reactions, and disease.


title: Virology of hepatitis C virus

text: Hepatitis C virus (HCV) has been identified as the main causative agent of post-transfusion non-A, non-B hepatitis. Through recently developed diagnostic assays, routine serologic screening of blood donors has prevented most cases of post-transfusion hepatitis. The purpose of this paper is to comprehensively review current information regarding the virology of HCV. Recent findings on the genome organization, its relationship to other viruses, the replication of HCV ribonucleic acid, HCV translation, and HCV polyprotein expression and processing are discussed. Also reviewed are virus assembly and release, the variability of HCV and its classification into genotypes, the geographic distribution of HCV genotypes, and the biologic differences between HCV genotypes. The assays used in HCV genotyping are discussed in terms of reliability and consistency of results, and the molecular epidemiology of HCV infection is reviewed. These approaches to HCV epidemiology will prove valuable in documenting the spread of HCV in different risk groups, evaluating alternative (nonparenteral) routes of transmission, and in understanding more about the origins and evolution of HCV.


Epidemiology and Treatment of Chronic Bronchitis and Its Exacerbations


title: Veterinary vaccines

text: Vaccination of animals for the prevention of infectious diseases has been practised for a number of years with little change in product composition. Recent advances in molecular biology, pathogenesis and immunology have laid the groundwork for the development of a new generation of veterinary vaccines based on pure subunits as well as live vectored bacteria and viruses. Along with novel methods of antigen preparation, the use of new adjuvants and delivery systems will permit targeting of the appropriate immune response as well as offering flexibility in terms of vaccination protocols. These new technologies are also being applied to the development of vaccines to enhance animal productivity and to control reproduction.


Distinctive features of foot-and-mouth disease virus, a member of the picornavirus family; aspects of virus protein synthesis, protein processing and structure


title: Diversity of coding strategies in influenza viruses

text: Influenza viruses have exploited a variety of strategies to increase their genome coding capacities. These include unspliced, spliced, alternatively spliced and bicistronic mRNAs, translation from overlapping reading frames and a coupled stop-start translation of tandem cistrons.


title: Structural organization, expression and chromosomal mapping of the mouse cystatin-C-encoding gene (Cst3)

text: Cystatin C (CstC) is a potent cysteine-proteinase inhibitor. The structure of the mouse CstC-encoding gene (Cst3) was examined by sequencing a 6.1-kb genomic DNA containing the entire gene, as well as 0.9 kb of 5′ flanking and 1.7 kb of its 3′ flanking region. The sequence revealed that the overall organization of the gene is very similar to those of the genes encoding human CstC and other type-2 Cst, with two introns at positions identical to those in the human gene. The promoter area does not contain typical TATA or CAAT ☐es. Two copies of a Spl-binding motif, GGGCGG, are present in the 5′ flanking region within 300 bp upstream from the initiation codon. A hexa-nucleotide, TGTTCT, which is a core sequence of the androgen-responsive element (ARE), is found in the promoter region. This region also contains a 21-nucleotide sequence, 5′-AGACTAGCAGCTGACTGAAGC, which contains two potential binding sites for the transcription factor, AP-1. The mouse Cst3 mRNA was detected in all of thirteen tissues examined by Northern blot analysis. Cst3 was mapped in the mouse to a position on distal chromosome 2.


title: Inactivation of viral antigens for vaccine preparation with particular reference to the application of binary ethylenimine

text: Viral antigens for human and veterinary vaccines are still inactivated with formaldehyde. This is not an ideal inactivant and the problems of formaldehyde inactivation of vaccines are discussed. Vaccines inactivated with aziridines are superior in safety and antigenicity. Aziridines inactivate viruses in a first-order reaction and the inactivation rate and endpoint can be determined. The preparation and application of the aziridine compound binary ethylenimine (BEI) and the necessary conditions for and controls of the inactivation process are described and discussed. A computer program has been written for assistance in the use of BEI for controlled inactivation of viral antigens.


title: Binding of Plasmodium falciparum 175-kilodalton erythrocyte binding antigen and invasion of murine erythrocytes requires N-acetylneuraminic acid but not its O-acetylated form

text: Sialic acid on human erythrocytes is involved in invasion by the human malaria parasite, Plasmodium falciparum. Mouse erythrocytes were used as a reagent to explore the question of whether erythrocyte sialic acid functions as a nonspecific negative charge or whether the sialic acid is a necessary structural part of the receptor for merozoites. Human erythrocytes contain N-acetylneuraminic acid (Neu5Ac), whereas mouse erythrocytes, which are also invaded by P. falciparum merozoites, contain 9-O-acetyl-N-acetylneuraminic acid (Neu5,9Ac(2)) and N-glycoloylneuraminic acid (Neu5Gc), in addition to Neu5Ac. We compared the effects of sialidase and influenza C virus esterase treatments of mouse erythrocytes on invasion and the binding of a 175-kDa P. falciparum protein (EBA-175), a sialic acid-dependent malaria ligand implicated in the invasion process. Sialidase-treated mouse erythrocytes were refractory to invasion by P. falciparum merozoites and failed to bind EBA-175. Influenza C virus esterase, which converts Neu5,9Ac(2) to Neu5Ac, increased both invasion efficiency and EBA-175 binding to mouse erythrocytes. Thus, the parasite and EBA-175 discriminate between Neu5Ac and Neu5,9Ac(2), that is, the C-9 acetyl group interferes with EBA-175 binding and invasion by P.falciparum merozoites. This indicates that sialic acid is part of a receptor for invasion.


title: Increased influenza A virus sialidase activity with N-acetyl-9-O-acetylneuraminic acid-containing substrates resulting from influenza C virus O-acetylesterase action()

text: Influenza virus type C (Johannesburg/1/66) was used as a source for the enzyme O-acetylesterase (EC 3.1.1.53) with several natural sialoglycoconjugates as substrates. The resulting products were immediately employed as substrates using influenza virus type A [(Singapore/6/86) (H1N1) or Shanghai/11/87 (H3N2)] as a source for sialidase (neuraminidase, EC 3.2.1.18). A significant increase in the percentage of sialic acid released was found when the O-acetyl group was cleaved by O-acetylesterase activity from certain substrates (bovine submandibular gland mucin, rat serum glycoproteins, human saliva glycoproteins, mouse erythrocyte stroma, chick embryonic brain gangliosides and bovine brain gangliosides). A common feature of all these substrates is that they contain N-acetyl-9-O-acetylneuraminic acid residues. By contrast, no significant increase in the release of sialic acid was detected when certain other substrates could not be de-O-acetylated by the action of influenza C esterase, either because they lacked O-acetylsialic acid (human glycophorin A, α(1)-acid glycoprotein from human serum, fetuin and porcine submandibular gland mucin) or because the 4-O-acetyl group was scarcely cleaved by the viral O-acetylesterase (equine submandibular gland mucin). The biological significance of these facts is discussed, relative to the infective capacity of influenza C virus.


title: Interaction of Viruses with Cell Surface Receptors

text: This chapter discusses the interaction of viruses with cell surface receptors. The rigorous characterizations of receptor–ligand interactions have been derived from binding studies of radiolabeled ligands in neuropharmacology and endocrinology. The definition of viral recognition sites as receptors involves three major criteria that are derived from models of ligand–receptor interactions: saturability, specificity, and competition. A variety of approaches have been used to study the interaction of viral particles with cell surface receptors or reception sites. A rigorous study of viral–receptor interactions requires the use of more than one technique as different approaches provide complementary information about viral binding. The chapter discusses membrane components that interact with viruses. The identification of the subviral components that are responsible for the binding of viruses to cell surfaces has preceded the structural understanding of the cellular receptors themselves. The chapter summarizes current data concerning the viral attachment protein (VAP) of selected viruses.


Preparation of Components


Committed to Care: Research Submitted to the National Abortion Federation’s 44th Annual Meeting


Touch Me Not: Physical Distancing in Radiology during COVID-19


There’s So Much More to Cats…


Reply to “Subcutaneous terbutaline as an alternative to aerosolized albuterol”


What’s next for nudging and choice architecture?


title: The Influence of the Variation in Sepsis Rate between Neonatal Intensive Care Units on Neonatal Outcomes in Very-Low-Birth-Weight Infants

text: Sepsis is commonly known to affect neonatal outcomes. We assessed how much center-to-center variability of the sepsis rate affects the outcomes of very-low-birth-weight infants (VLBWIs). 7,493 VLBWIs registered in the Korean Neonatal Network from 2013 to 2016 were classified into three groups according to the sepsis rate: low sepsis group (LS) < 25(th) percentile versus intermediate sepsis group (IS) 25(th)–75(th) versus high sepsis group (HS) ≥ 75(th). The incidence density of sepsis for the LS, IS, and HS groups were 1.17, 3.17, and 8.88 cases/1,000 person-days. After propensity score matching was done for multiple antenatal and perinatal factors, the odds ratio of death, moderate to severe bronchopulmonary dysplasia and/or death, periventricular leukomalacia, and survival without major morbidities for the HS group were 2.0 (95% confidence interval 1.4–2.8), 1.9 (1.5–2.4), 1.5 (1.1–2.3) and 0.7 (0.5–0.8) when compared with the IS group, and 2.2 (1.6–3.2), 2.3 (1.8–2.9), 2.0 (1.3–2.9), and 0.7 (0.6–0.9) when compared with the LS group. There were no significant differences in those outcomes between the LS and IS groups. Hence, nationwide quality improvements to control the sepsis rate especially in units with a high sepsis rate will be helpful to improve the outcomes of VLBWIs.


Corona-Krise trifft auf Strukturprobleme im Gesundheitswesen


title: Wirtschaft unter Schock — Finanzpolitik hält dagegen

text: According to the leading German economic research institutes, the German economy is experiencing a drastic slump as a result of the corona pandemic. In order to slow down the wave of infection, the state has severely restricted economic activity in Germany. As a result, GDP is expected to shrink by 4.2% this year. The recession is leaving clear traces on the labour market and the national budget. At its peak, the unemployment rate will soar to 5.9% and the number of short-time workers to 2.4 million. This year, the fiscal policy stabilisation measures will lead to a record deficit in the general government budget of 159 billion euro. After the shutdown, the economy will gradually recover. Accordingly, the increase in GDP next year will be strong at 5.8%. This forecast is associated with considerable downside risks, e.g. because the pandemic can be slowed faster or because the recovery of economic activity will be less successful than expected or there may be a new wave of infection.


Vermögensverteilung und Wirtschaftskrisen


Nachfrageorientierte Klimapolitik — Evidenz aus der Corona-Krise


Steigende Einkommen, sinkende Sorgen — die Zeit vor Corona


Sicherheit in unsicheren Zeiten


title: Human Influenza Virus Infections

text: Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection.


title: In Vivo Assembly of Nanoparticles Achieved through Synergy of Structure‐Based Protein Engineering and Synthetic DNA Generates Enhanced Adaptive Immunity

text: Nanotechnologies are considered to be of growing importance to the vaccine field. Through decoration of immunogens on multivalent nanoparticles, designed nanovaccines can elicit improved humoral immunity. However, significant practical and monetary challenges in large‐scale production of nanovaccines have impeded their widespread clinical translation. Here, an alternative approach is illustrated integrating computational protein modeling and adaptive electroporation‐mediated synthetic DNA delivery, thus enabling direct in vivo production of nanovaccines. DNA‐launched nanoparticles are demonstrated displaying an HIV immunogen spontaneously self‐assembled in vivo. DNA‐launched nanovaccines induce stronger humoral responses than their monomeric counterparts in both mice and guinea pigs, and uniquely elicit CD8+ effector T‐cell immunity as compared to recombinant protein nanovaccines. Improvements in vaccine responses recapitulate when DNA‐launched nanovaccines with alternative scaffolds and decorated antigen are designed and evaluated. Finally, evaluation of functional immune responses induced by DLnanovaccines demonstrates that, in comparison to control mice or mice immunized with DNA‐encoded hemagglutinin monomer, mice immunized with a DNA‐launched hemagglutinin nanoparticle vaccine fully survive a lethal influenza challenge, and have substantially lower viral load, weight loss, and influenza‐induced lung pathology. Additional study of these next‐generation in vivo‐produced nanovaccines may offer advantages for immunization against multiple disease targets.


title: 1H-Imidazole-2,5-Dicarboxamides as NS4A Peptidomimetics: Identification of a New Approach to Inhibit HCV-NS3 Protease

text: The nonstructural (NS) protein NS3/4A protease is a critical factor for hepatitis C virus (HCV) maturation that requires activation by NS4A. Synthetic peptide mutants of NS4A were found to inhibit NS3 function. The bridging from peptide inhibitors to heterocyclic peptidomimetics of NS4A has not been considered in the literature and, therefore, we decided to explore this strategy for developing a new class of NS3 inhibitors. In this report, a structure-based design approach was used to convert the bound form of NS4A into 1H-imidazole-2,5-dicarboxamide derivatives as first generation peptidomimetics. This scaffold mimics the buried amino acid sequence Ile-25` to Arg-28` at the core of NS4A(21`–33`) needed to activate the NS3 protease. Some of the synthesized compounds (Coded MOC) were able to compete with and displace NS4A(21`–33`) for binding to NS3. For instance, N(5)-(4-guanidinobutyl)-N(2)-(n-hexyl)-1H-imidazole-2,5-dicarboxamide (MOC-24) inhibited the binding of NS4A(21`–33`) with a competition half maximal inhibitory concentration (IC(50)) of 1.9 ± 0.12 µM in a fluorescence anisotropy assay and stabilized the denaturation of NS3 by increasing the aggregation temperature (40% compared to NS4A(21`–33`)). MOC-24 also inhibited NS3 protease activity in a fluorometric assay. Molecular dynamics simulations were conducted to rationalize the differences in structure–activity relationship (SAR) between the active MOC-24 and the inactive MOC-26. Our data show that MOC compounds are possibly the first examples of NS4A peptidomimetics that have demonstrated promising activities against NS3 proteins.


title: Therapeutic management of severe hypothermia with veno-arterial ECMO: where do we stand? Case report and review of the current literature

text: BACKGROUND: Severe accidental hypothermia is associated with high morbidity and mortality. Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) provides an efficient rewarming method with complete cardiopulmonary support. The use of VA-ECMO for this indication has greatly improved the vital and functional prognosis of patients. CASE PRESENTATION: We report a case of a 46-year-old patient who was treated for severe hypothermia with a temperature of 22.4 °C along with initial cardiac arrest, whose progression was favorable after the implementation of VA-ECMO support. Two months after initial cardiac arrest, the patient was reassessed and showed signs of complete recovery with regard to his mental and physical capacities. CONCLUSIONS: The recent international publications and groups of experts recommend the use of VA ECMO as the gold standard therapy to treat severe hypothermia. Therefore, it seems suitable to update the current knowledge on the topic by analysing the latest international publications. The performance of this technique calls into question ethical and economic factors. Two distinct medical teams tried to identify and regroup prognosis factors in predictive survival scores. They raise the question of the utility of these scores in clinical practice. Indeed, according to which survival rate should we proceed to prolonged resuscitation and implement VA-ECMO? Additional studies will be needed for external approval of these survival scores, and additional reflection by experts will be required.


title: Clinical efficacy and safety of polymyxins based versus non-polymyxins based therapies in the infections caused by carbapenem-resistant Acinetobacter baumannii: a systematic review and meta-analysis

text: BACKGROUND: The prevalence of infections due to carbapenem-resistant Acinetobacter baumannii (CRAB) is on the rise worldwide. Polymyxins are considered as last-resort drugs for CRAB infections, but there is still controversy regarding the efficacy and safety of polymyxins based therapies in CRAB infections. The present systematic review was designed to compare the efficacy and safety of polymyxins based therapies versus non-polymyxins based therapies in CRAB infections. METHODS: We performed a systematic literature search in PubMed, Embase, CINAHL, Cochrane Library, and clinicaltrials.gov to identify eligible studies reporting the clinical outcomes of patients with CRAB infections. The meta-analysis employed a random-effects model to estimate the odds ratio (OR) and standardized mean difference (SMD) with 95% confidence interval (CI). The primary outcome was 1-month mortality for any cause. We also examined clinical response, microbiological response, length of stay in hospital, and adverse events. RESULTS: Eleven eligible studies were analyzed (1052 patients in total), including 2 randomized clinical trials. Serious risk of bias was found in 8 out of the 11 studies. There was no statistically significant difference between polymyxins based therapies and non-polymyxins based therapies in 1-month mortality for any cause (OR, 0.95; 95% CI, 0.59 to 1.53), microbiological response (OR, 3.83; 95% CI, 0.90 to 16.29) and length of stay in hospital (SMD, 0.24; 95% CI, − 0.08 to 0.56). The pooled OR of clinical response indicated a significant difference in favor of polymyxin based therapies (OR, 1.99; 95% CI, 1.31 to 3.03). The pooled OR of adverse events showed that non-polymyxins based therapies were associated with fewer adverse events (OR, 4.32; 95% CI, 1.39 to 13.48). CONCLUSION: The performance of polymyxins based therapies was better than non-polymyxin based therapies in clinical response rate and similar to non-polymyxin based therapies in terms of 1-month mortality and microbiological response in treating CRAB infections. Due to the limitations of our study, we cannot draw a firm conclusion on the optimal treatment of CRAB infections, but polymyxins would be a relatively effective treatment for CRAB infections. Adequate and well-designed large scale randomized controlled trials are required to clarify the relative efficacy of polymyxins based and non-polymyxins based therapies.


title: Severity and outcomes of influenza-related pneumonia in type A and B strains in China, 2013–2019

text: BACKGROUND: Inconsistencies exist regarding the severity of illness caused by different influenza strains. The aim of this study was to compare the clinical outcomes of hospitalized adults and adolescents with influenza-related pneumonia (Flu-p) from type A and type B strains in China. METHODS: We retrospectively reviewed data from Flu-p patients in five hospitals in China from January 2013 to May 2019. Multivariate logistic and Cox regression models were used to assess the effects of influenza virus subtypes on clinical outcomes, and to explore the risk factors of 30-day mortality for Flu-p patients. RESULTS: In total, 963 laboratory-confirmed influenza A-related pneumonia (FluA-p) and 386 influenza B-related pneumonia (FluB-p) patients were included. Upon adjustment for confounders, multivariate logistic regression models showed that FluA-p was associated with an increased risk of invasive ventilation (adjusted odds ratio [aOR]: 3.824, 95% confidence interval [CI]: 2.279–6.414; P < 0.001), admittance to intensive care unit (aOR: 1.630, 95% CI: 1.074–2.473, P = 0.022) and 30-day mortality (aOR: 2.427, 95% CI: 1.568–3.756, P < 0.001) compared to FluB-p. Multivariate Cox regression models confirmed that influenza A virus infection (hazard ratio: 2.637, 95% CI: 1.134–6.131, P = 0.024) was an independent predictor for 30-day mortality in Flu-p patients. CONCLUSIONS: The severity of illness and clinical outcomes of FluA-p patients are more severe than FluB-p. This highlights the importance of identifying the virus strain during the management of severe influenza.


title: Latest trends in L. infantum infection in dogs in Spain, Part II: current clinical management and control according to a national survey of veterinary practitioners

text: BACKGROUND: Canine leishmaniosis (CanL) is a parasitic zoonotic disease, endemic in the Mediterranean basin including Spain. While knowledge about CanL, its management, treatment, prevention and control mounts, it remains unclear whether all clinical veterinarians follow the same international recommendations, such as those of the LeishVet group. This study was thus designed to assess recent trends in the clinical management of CanL in veterinary clinics across Spain through a questionnaire-based survey. Results were compared with those of a prior national multicenter questionnaire administered by our research team in 2005. METHODS: A questionnaire consisting of 28 questions about CanL was developed using Google Forms and distributed by email to 1428 veterinary clinics in Spain. Questions were designed to obtain data on common clinical signs, techniques and complementary exams used to diagnose the disease, and on its monitoring, treatment and control measures. Data were collected in a database for statistical analysis. RESULTS: Completed questionnaires were returned by 295 clinics. Compared to the situation in 2005, responses indicate that clinical signs of CanL have not changed significantly, cutaneous lesions being still the most prevalent sign observed by practitioners. Quantitative serological techniques are considered an adequate approach to diagnosis, provided their results are supported by the findings of a thorough physical exam, as well as complementary tests (complete blood count, biochemical profile, plasma protein electrophoretogram and complete urinalysis). Treatment protocols and check-ups follow international recommendations. Finally, a multimodal approach is being endorsed to adequately control CanL including preventive measures such as annual serological check-ups and the combination of repellents and vaccines. Additionally, owners are being better informed about CanL by veterinarians, which translates to the improved control of this zoonosis. CONCLUSIONS: The clinical management of CanL has recently undergone significant changes owing to improvements in clinical knowledge of the disease, more unified international criteria, improved diagnostic techniques and their adequate interpretation, as well as a greater awareness of the disease transmitted to owners. [Image: see text]


title: Public health response to two imported, epidemiologically related cases of Lassa fever in the Netherlands (ex Sierra Leone), November 2019

text: On 20 November 2019, Lassa fever was diagnosed in a physician repatriated from Sierra Leone to the Netherlands. A second physician with suspected Lassa fever, repatriated a few days later from the same healthcare facility, was confirmed infected with Lassa virus on 21 November. Comprehensive contact monitoring involving high- and low-risk contacts proved to be feasible and follow-up of the contacts did not reveal any case of secondary transmission in the Netherlands.


Mulling over meetings


Meetings - A European view


title: Net woody vegetation increase confined to seasonally inundated lowlands in an Australian tropical savanna, Victoria River District, Northern Territory

text: Abstract Georeferenced digital aerial photographs were used to assess changes in overstorey vegetation cover since 1948 in the Victoria River District, Northern Territory, Australia, across a range of lowland tropical savanna habitats and with explicit consideration of known and variable site‐specific grazing and fire management histories. Vegetation surveys at corresponding locations on the ground identified five distinct woody vegetation communities defined primarily by water drainage and secondarily by soil characteristics. Air‐photo analyses revealed that, contrary to popular perceptions and in contrast to results from other habitats, there has been no generalized net increase in overstorey woody vegetation cover across the full range of lowland savanna habitats. Rather, different habitats exhibited distinctly different vegetation change mechanisms: low‐lying seasonally inundated ‘wet’ habitats have experienced woody vegetation increase since 1948, whereas well‐drained ‘dry’ habitats have experienced overstorey vegetation stability or loss. In almost every instance woody vegetation increase could be attributed to the invasion or proliferation of a single species, Melaleuca minutifolia F.Muell. The extent of M. minutifolia increase was unrelated to historical grazing/fire regime. Demographic analyses for this species revealed that recruitment was often episodic and that synchronized recruitment events occurred uniformly across the full range of historical management treatments, most likely as a consequence of favourable climatic conditions in years with an extended wet season. Heavy grazing facilitated juvenile survival and/or recruitment, most likely by reducing grassy fuel loads and eliminating landscape fire. We conclude that while there has been no generalized net increase in overstorey woody vegetation cover in lowland environments, savanna dynamics are complex, and multiple change mechanisms have occurred simultaneously in different habitats, some of which have been significantly transformed since 1948. Where net woody vegetation increase has occurred it is primarily a natural consequence of episodic M. minutifolia establishment in climatically favourable years, but the extent and magnitude of this effect is likely mediated by fire/grazing regime.


title: Habitat structure is more important than vegetation composition for local‐level management of native terrestrial reptile and small mammal species living in urban remnants: A case study from Brisbane, Australia

text: Abstract As urban areas continue to expand and replace natural and agricultural landscapes, the ability to manage and conserve native wildlife within urban environments is becoming increasingly important. To do so we first need to understand species' responses to local‐level habitat attributes in order to inform the decision‐making process and on‐ground conservation actions. Patterns in the occurrence of native terrestrial reptile and small mammal species in 59 sites located in remnant urban habitat fragments of Brisbane City were assessed against local‐level environmental characteristics of each site. Cluster analysis, multidimensional scaling ordination, and principal axis correlation were used to investigate relationships between species' occurrences and environmental characteristics. Native reptiles were most strongly associated with the presence of termite mounds, a high amount of fallen woody material, and a moderate amount of weed cover. Native small mammals were most strongly associated with the presence of grass trees (Xanthorrhoea spp.), and both reptiles and small mammals were negatively influenced by increased soil compaction. Significant floristic characteristics were considered to be important as structural, rather than compositional, habitat elements. Therefore, habitat structure, rather than vegetation composition, appears to be most important for determining native, terrestrial reptile and small mammal species assemblages in urban forest fragments. We discuss the management implications in relation to human disturbances and local‐level management of urban remnants.