Background: Dyslipidemia is a common comorbidity and an important risk factor for myocardial infarction (MI). This study aimed to examine the economic burden of MI combined with dyslipidemia in China.Methods: Patients who were hospitalized due to MI combined with dyslipidemia in 2016 were enrolled. Costs were measured based on electronic medical records and questionnaires. The annual costs were analyzed by conducting descriptive statistics, univariable, and multivariable analyses.Results: Data of 900 patients were analyzed, and 144 patients were dead during the follow-up. The majority of patients were aged 51–70 years  and males . For all-cause costs, the median annual direct medical costs, direct non-medical costs, indirect costs, and total costs were RMB 13,168 , RMB 600 , RMB 676 , RMB 15,361 , respectively; while for cardiovascular-related costs, the corresponding costs were RMB 12,233 , RMB 515 , RMB 587 , and RMB 14,223 , respectively. Lifestyle and complications significantly affected both all-cause costs and cardiovascular-related costs.Conclusions: Increasing attention should be paid to encourage healthy lifestyle, and evidence-based medicine should focus on optimal precautions and treatments for complications, to reduce the economic burden among MI patients with a comorbid dyslipidemia. There are ~290 million cardiovascular patients in China, including 11 million patients with coronary atherosclerotic heart disease, in which myocardial infarction (MI) is the most acute and dangerous disease (Dyslipidemia is one of the most significant risk factors for MI. Patients with a history of MI are at high risk and should strictly control their low-density lipoprotein-cholesterol levels (LDL-C) , 4. AccoMI, in turn, carries a heavy economic burden. In 2014, the annual direct medical costs of cardiovascular and cerebrovascular diseases in China exceeded 130 billion yuan, accounting for over 22% of the total medical costs in the same year . At presStudies on the burden of disease in China only focus on patients' hospitalization costs. There has been no relevant study on this extremely high-risk population of MI with dyslipidemia. Therefore, this study combined patients' medical records and questionnaires to investigate the economic burden for patients with MI and dyslipidemia in China's real-world environment. Our research filled the literature gap by providing the most recent data on the economic burden of MI combined with dyslipidemia from the social perspective, and the factors that potentially impact economic burden were analyzed. Therefore, our results may highlight the importance of providing prevention measures and management intervention. The up-to-date data may be used as important cost parameters for economic evaluations, such as cost of illness or cost-effectiveness/utility analysis.This is a multicenter study combining retrospective cohort and cross-sectional research and was conducted from a social perspective. Six tertiary hospitals from major cities—Beijing, Shanghai, Wuhan, Nanjing, Guangzhou, and Chengdu, China were chosen as research centers for data collection.Data were collected according to medical record review and questionnaires, including demographic characteristics , lifestyle , disease characteristics , hospitalization costs and costs of outpatient . As the simplified questionnaires were used for the deceased, information, such as lifestyle, income, accommodation and transportation expenses, and out-of-hospital visits were not collected and not able to be analyzed accordingly. The medical record review and questionnaires were linked by patients' name as well as the unique ID number or medical card number.For all patients, their first hospitalization from January 1, 2016 to December 31, 2016 was considered as the index event, and their related 1-year post-index data was collected and analyzed. Key information of the data is shown in The study was approved by the Ethics Committees of all the six participating hospitals. Written informed consent was provided by all participants before the data collection and conduction of the research. Before analysis, the patient data were anonymized and de-identified.Inclusion criteria in this study included: patients hospitalized with myocardial infarction (MI) from January 1, 2016 to December 31, 2016. The earliest hospitalization was considered as the index hospitalization; patients for whom in the first blood lipid examination of the index hospitalization, the LDL-C was ≥1.8 mmol/L or were using lipid-regulating drugs. Exclusion criteria included: patients who died during the index hospitalization; patients who participated in clinical trials after the index hospitalization; patients or family members (if the patient had died) who were not willing to participate in survey or could not correctly understand and answer relevant questions due to communication barriers.This study's primary outcomes were the annual total costs of survivors and deceased, which were reported in all-cause and CV-related costs, as well as the direct medical, direct non-medical, and indirect costs. Here CV-related indicates cardiovascular diseases, including MI, hypertension, post-percutaneous transluminal coronary intervention (PCI), peripheral arterial disease, etc. The secondary outcomes were the influencing factors for the annual total all-cause and CV-related costs of survivors.Direct medical costs included registration, diagnosis, examination, medicine (including pharmacy purchase), operation, bed fee, material, nursing, and other expenses. The direct medical costs were obtained through electronic medical records. Out-of-hospital direct medical costs of the survivors were obtained through questionnaires, while the deceased's out-of-hospital direct medical costs were not collected.Direct non-medical costs included expenses related to patient caregivers, accommodation and transportation, and health care products, etc. The survivors' data were collected through questionnaires, while the data of the deceased were not collected.Indirect costs were calculated by the human capital method  to calcuDescribed for the baseline characteristics and costs by survival status. Categorical variables were reported as numbers and proportions, and continuous variables were reported as medians and interquartile ranges.Univariable and multivariable analyses were applied to the study of the economic burden's influencing factors. In the univariable analysis, the chi-square test was performed for categorical variables; the Wilcoxon rank-sum test or the Kruskal-Wallis test was used for continuous variables.Multivariable analysis was performed in generalized linear model (GLM) with gamma distribution and log link function. Multivariable analysis was not performed for the deceased's total annual costs due to the lack of certain baseline information. Patients' baseline information , lifestyle , and disease history  were included as independent variables in GLM. The annual all-cause and CV-related total costs of survivors were used as dependent variables.We combined some variables' classifications in the multivariable analysis since some variables had too many original categories. (a) Medical insurance types: BMISUE, BMISUR, and NRCMS were combined into one category . (b) Education status: not graduated from primary school, primary school were combined into primary education; Junior high school, high school, technical secondary school/junior college graduate were combined into medium education; Bachelor, master and doctor were combined into high education. (c) Marital status: unmarried, divorce, and death of a spouse were combined into current single. (d) Employment status: formal employees, individuals, and freelancers were combined into formal wage; Farming, unemployed were combined into non-formal wage.P < 0.05 with a two-tailed test. Data were analyzed using Stata SE 15  and SPSS 22.0 .The significance level was set at The baseline information of patients is shown in n = 706, 78.44%) than females . The average age of all patients was 62.07 years (SD: 11.45), and patients aged 60–70 years were the majority . In terms of body mass index (BMI), most patients  were overweight (23.9 < BMI ≤ 27.9) or obese (BMI > 27.9) . Regarding the medical history, 94.67% (n = 852) patients were of first-episode MI, 64.67% (n = 582) had undergone PCI, and most complications were hypertension , type 2 diabetes , and lipid metabolism disorder . For the type of medical insurance, 88.33% (n = 795) had one of the following basic medical insurance which covered majority people in China: basic medical insurance system for urban employees (BMISUE), basic medical insurance system for urban residents (BMISUR), and the new rural cooperative medical system (NRCMS).There were more males  were of moderate degree , most  were married, up to 66.53% (n = 503) were retirees, 49.86% had income more than RMB 2,400 and less than RMB 5,500. In terms of lifestyle, the majority had no history of smoking  or drinking , often ate high-fiber foods and grains  and controlled high-fat and high-cholesterol food intake ; 61.77% (n = 467) often exercised.Among the 756 surviving patients, the majority , RMB 9,341 , RMB 14,223 . The corresponding average annual costs were RMB 15,480 , RMB 12,759 , and RMB 28,777 , respectively.The median annual ratio of CV-related costs to all-cause costs was high. The direct medical costs and the hospitalization costs accounted for the largest proportion of total costs.The univariable analysis results of the annual all-cause and CV-related costs of survivors are shown in P = 0.049), employment status (P = 0.023), income levels (P = 0.036), smoking status (P = 0.016), drinking status (P = 0.016), and dietary control conditions (P = 0.020). Complications, such as hypertension (P = 0.005), type 2 diabetes (P = 0.000), and PCI (P = 0.033) significantly affected the annual all-cause total costs. Regarding CV-related costs, patients with different smoking status (P = 0.009) and complications including hypertension (P = 0.003) and type 2 diabetes (P = 0.014) had significantly different costs.For the survivors, there were significant differences in the annual all-cause costs among patients with different age groups (P = 0.021), BMI (P = 0.049), and medical insurance type (P = 0.041). In addition, substantial differences existed in the annual CV-related costs among patients with different BMIs (P = 0.019) and lipid metabolism disorders (P = 0.049).For the deceased, there were significant differences in the annual all-cause costs among patients with different causes of death (P > 0.05), indicating that the two GLM models fit well.In the GLM model of annual all-cause total costs, 743 patients whose total costs were not 0 without missing categorical variable data were included. In the GLM model of annual CV-related total costs, 741 patients whose total costs were not 0 without missing categorical variable data were included. In the goodness of fit test of the models, the significance levels calculated by the Deviance test and Pearson Chi-Square test were respectively 1.188 and 1.446 for the all-cause model, 1.277 and 1.415 for the CV-related model, none of which were significant (P = 0.003), and was more than RMB 5,500 (P = 0.005), who sometimes did sports (P = 0.030) had significantly higher total costs. Having type 2 diabetes (P = 0.012) was also influencing factors that significantly increased the all-cause total costs. Patients who sometimes (P = 0.002) and often (P = 0.047) smoke, sometimes control high-fat and high-cholesterol diet (P = 0.016) had significantly lower total costs. Having PCI (P = 0.000) was also influencing factors that significantly decreased the all-cause total costs.The multivariable analysis results for annual all-cause and CV-related total costs of the survivors are shown in P = 0.002), and was more than RMB 5,500 (P = 0.010), who sometimes did sports (P = 0.036) had significantly higher total costs. Having type 2 diabetes (P = 0.012) was also influencing factors that significantly increased the all-cause total costs. Patients who sometimes (P = 0.003) and often (P = 0.005) smoke had significantly lower total costs. Having MI history (P = 0.045) and PCI (P = 0.012) was also influencing factors that significantly decreased the all-cause total costs.While for annual CV-related costs, patients with basic medical insurance, patients whose income per month was more than RMB 2,400 and less than RMB 4,000 . The median annual all-cause and CV-related costs of hospitalization and outpatient of patients are reported, allowing readers to understand the economic burden of this population multi-dimensionally.Our study also has some limitations. First, data on direct non-medical costs and indirect costs were derived from questionnaires, which can be more subjective than written or electronically recorded data. Second, specific costs regarding medical insurance reimbursement and out-of-pocket were missing; therefore, it was impossible to compare and analyze the out-of-pocket and medical insurance fund expenditures in this study.Chinese patients with MI combined with dyslipidemia have high all-cause and CV-related costs, among which hospitalization and direct medical costs account for a large proportion. Our findings suggest that a healthy lifestyle contributes a lot and optimal precautions and treatments for complications should be emphasized, which can help to reduce the economic burden. It is also anticipated that the descriptive annual costs will act as a significant new resource for the cost-of-illness studies as well as economic evaluations regarding this population.lihongchao@cpu.edu.cn.The datasets generated for this article are not readily available because sharing of raw data would be contingent on approval from the research ethics office because of the ethics consideration. Requests to access the datasets should be directed to The studies involving human participants were reviewed and approved by Peking University First Hospital; Wuhan Asia Heart Hospital; Guangdong Provincial People's Hospital; Nanjing Gulou Hospital; Sichuan Provincial People's Hospital; Zhongshan Hospital, Fudan University. The patients/participants provided their written informed consent to participate in this study.HL, AM, and PC designed this study. Data were collected and managed by YZ, XS, JC, BX, JT, and ZW. PC and MZ performed the statistics using software and drafted the manuscript. HL and AM supervised the data analysis and proposed suggestions for revising the manuscript. All authors critically reviewed the manuscript, approved the final version of the manuscript, and agreed to be accountable for the content of the work.Amgen Biotech Consultation (Shanghai) Co., Ltd partly sponsored this study. However, this study is an economic burden investigation, which does not involve any specific products. Therefore, the authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Neurotropic viruses are those viruses that can cause central nervous system (CNS) diseases with both neuroinvasive and neurovirulence properties. It comprises a wide range of viruses, including herpes simplex virus, poliovirus, enteroviruses, parechovirus, West Nile virus, Japanese encephalitis virus, measles, and mumps viruses among others. Some of these viruses are highly neuroinvasive and neurovirulent, while others are weakly neuroinvasive and neurovirulent. Moreover, some of them, like herpes simplex viruses, are highly neuroinvasive but weakly neurovirulent for the peripheral nervous system and highly neurovirulent but weakly neuroinvasive for the central nervous system. All these disparities are a result of differences in their genomic constitution, associated vectors, geographical region, and environmental factors. Therefore, a successful intervention will be almost impossible without a clear understanding of the molecular biology and epidemiology of these viruses. Thus, we conducted a review of the published studies on the molecular biology and epidemiology of the common neurotropic viruses to make the viral genetic makeup more understandable for targeted intervention and provide the morbidity and mortality data of the different neurotropic viruses for more serious action. A large number of viruses have been implicated in many neurological diseases in different parts of the world which were shown to disrupt the anatomy and physiology of the central nervous system (CNS), resulting in deformity and a high fatality rate. Therefore, effective therapeutic measures are needed to address the problems caused by these viruses, which can only be achieved if the molecular biology and the epidemiology of the viruses are fully understood. Their geographical distribution largely determines the incidence and prevalence of neurological diseases caused by these viruses. In America, for example, the annual incidence of viral meningitis is higher than the incidence of meningitis caused by all other pathogens, reaching more than 10,000 cases annually up to 75,000 cases .Viral infections of the central nervous system have been emerging. Re-emerging infections and the clinical spectrum mainly depend on certain factors, which include the viral genomic constitution, the geographical location of the viral vector, host immune status, and some environmental factors. However, they are commonly misdiagnosed and their etiology frequently missed, partly due to a lack of proper diagnostic apparatus and partly due to poor understanding of the viral biology and their epidemiology . The etiIn this review, we focus on the molecular biology and the epidemiology of the different viruses that can potentially cause neurological diseases. We review the current understanding of the different neurotropic viruses from the different viral families and their neurotropic members to the structure and composition of the viral genome, the geographical distribution of the different viruses, and then down to the worldwide prevalence and incidence. We also aim to outline the morbidity and mortality profile of the different neurotropic viruses and the contributing epidemiological factors in the spread and outbreaks of these viruses. Therefore, the overall objective of the paper is to give a complex picture of the different neurotropic viruses, elucidating on their genetic composition, viral replication, geographical location, and their demographic profile, which will immensely help in understanding the mechanism employed by the viruses during neuroinvasion and neurovirulence.PicornavirusesMolecular BiologyPicornaviruses, one of the largest virus families, are small (30 nm in size), single-stranded, non-enveloped ribonucleic viruses that contain 29 genera with EVs and Parechoviruses (PeVs) as human pathogenic genera. The genus EV is divided into 13 species designated as EV A-J and Rhinoviruses (RVs) A-C, of which seven (EV A-D and RV A-C) are human pathogens, and the remaining six (EV E-J) were shown to infect only animals -6. The sThe viral genome of Picornaviruses is a single, open reading frame with highly structured untranslated regions (UTRs) at the 5- and 3-ends, it is uncapped, and the 5′-end is covalently coupled to the viral protein 3B, hence called viral protein genome (VPg)-linked. The setting of the open reading frame is similar in all Picornaviruses, with some differences between genera and some species. The genus EV consists of a simple viral capsid constructed in 60 repeating protomers, each of which contains four structural proteins VP 1 - 4), that collectively form an icosahedral shell [ - 4, thaEpidemiologyThe human pathogenic Picornaviruses (EVs and PeVs) constitute the major causes of aseptic meningitis in children, especially in neonates and young infants . Human EArbovirusesMolecular BiologyAs the name implies, arboviruses are arthropod-borne viruses with a worldwide distribution that encompasses hundreds of heterogeneous groups of about 537 viruses. They are also called tick-borne viruses. Most arboviruses have a ribonucleic acid (RNA) genome that has higher genetic plasticity and mutational rate , 13-14. 1) Togaviridae: The clinically important viruses in this group belong to the genus alphavirus which consists of the following species: Eastern equine encephalitis virus (EEEV), Western equine encephalitis virus (WEEV), and Venezuelan equine encephalitis virus (VEEV), as well as the Mayaro virus (MAYV), Una virus (UNAV), and Chikungunya virus (CHIKV). The first groups are called New World alphaviruses, while the second groups are called Old World. Alphaviruses are small, enveloped viruses with a single-stranded, positive-sense RNA genome that has 5’ cap and 3’ poly-A tail with two open reading frames that are translated into two polyproteins comprising structural and nonstructural proteins, respectively -14.2) Flaviviridae: The word flavus comes from the Latin word meaning yellow, as observed in the yellow fever virus infection. Flaviviruses are very diverse, consisting of the world's clinically most important viruses and consist of the following species: Japanese encephalitis virus (JEV), tick-borne encephalitis virus (TBEV), and Powassan encephalitis virus (POWV), as well as other mosquito-borne viruses, such as the Dengue virus (DENV), yellow fever virus (YFV), West Nile virus (WNV), St. Louis encephalitis virus (SLEV), and Zika virus (ZIKV). Hence, broadly, there are two forms of flaviviruses: tick-borne and mosquito-borne flaviviruses. They are enveloped structured, single-stranded, positive-sense RNA viruses with a single open reading frame which is translated into a polyprotein that is cleaved into mature structural and nonstructural polypeptides by viral and host proteases .3) Bunyaviralis: The family Bunyaviralis consists of three main genera - Nairovirus with a species of Crimean-Congo hemorrhagic fever (CCHF); orthobunyaviruses with species of California encephalitis virus (CEV), Jamestown Canyon virus (JCV), and La Crosse encephalitis (LACV); and phleboviruses with species of Toscana virus (TOSV) and Rift Valley fever virus (RVFV). The Bunyaviruses are enveloped particles of about 80 - 120 nm containing a negative-sense, single-stranded RNA genome. They are tripartite, containing three segments, each in its nucleocapsid structure .4) Reoviridae: The family Reoviridae is divided into two main subfamilies with many genera: Sedoreovirinae  and Spinareovirinae . The genus Orbivirus is the most clinically important genus with species of Colorado tick fever virus (CTFV). They are double-stranded segmented RNA viruses. The virion is nonenveloped and divided into 12 segments, with each viral family utilizes distinct strategies for infection and replication .EpidemiologyMany arboviruses have been identified worldwide, with the global distribution determined mainly by the biology of the vectors and the animal reservoirs. Transmission occurs throughout the year and is affected by the changes in environmental conditions, such as temperature, rainfall, humidity, and vegetation , 14. Arb1) Togaviridae/Alphaviruses: The transmission of alphaviruses causing encephalitis typically occurs between mosquitoes and birds (EEEV and WEEV), mosquitoes and rodents (VEEV enzootic cycle), or mosquitoes and horses (VEEV epizootic cycle). When humans contract the infection, it rapidly progresses to encephalitis with a fatality of about 1% in cases of VEEV and WEEV and 50% to 75% in cases of EEEV. Alphaviruses have a global distribution and are typically classified into Old and New Worlds. The New World alphaviruses are found in the American continent and are the ones causing encephalitis, whereas the Old World are found in Europe, Asia, and part of Africa with few members, like CHIKV, causing encephalitis. The most important neurotrophic alphavirus is VEEV, which caused many outbreaks in South, Central, and North America . CHIKV i2) Flaviviridae: Flaviviruses are transmitted by both ticks and mosquitoes, hence classified into tick-borne flaviviruses and mosquito-borne flaviviruses. The former includes the tick-borne encephalitis virus (TBEV) and Powassan encephalitis virus (POWV), while the latter includes JEV, DENV, WNV, YFV, SLE, and ZIKV. Tick-borne flaviviruses have been considered medically important as they cause about 10,000 to 15,000 human cases every year in Europe and Asia .Tick-borne encephalitis (TBE), caused by TBEV, is mainly a central nervous system infection that is transmitted to humans by the bites of ticks. The incidence is progressively increasing in European and Asian countries with serious neurological complications. POWV is a tick-borne flavivirus, similar to TBEV, caused by the bite of Ixodesscapularis, Ixodes cookei (I. cookei), and Ixodes marxi ticks (I. marxi ticks) and transmission occurs very quickly (approximately 15 minutes after tick attachment) .Japanese encephalitis (JE) virus is associated with high morbidity and mortality in infants, and about 2 billion people were reported to be affected annually in tropical and subtropical countries. Most of the cases are reported annually from the People’s Republic of China (PRC), Korea, Japan, Indonesia, Cambodia, Thailand, Vietnam, Malaysia, and countries belonging to the Indian subcontinent, and parts of Oceania with at least 700 million potentially susceptible children . OrnithoWest Nile virus (WNV), which was identified first in the West Nile subregion of Uganda, is now endemic in temperate and tropical regions throughout the world, causing yearly outbreaks of encephalitis, with a mortality rate of 5% to 10%. Ornithophilic mosquitoes generally transmit JEV; however, it can also be transmitted via blood transfusion or transplacentally to the fetus during pregnancy . WNV hasDengue virus (DENV) has a worldwide distribution resulting from human migration, uncontrolled urbanization, armed conflict, inadequate waste and water management, and unsustainable vector control. It is endemic in more than 100 countries and is transmitted to humans by the female mosquitoes of the genus Aedes (Ae), mainly Ae. aegypti and Ae. albopictus, during a blood meal. It is divided generally into four genetically related but antigenically different groups, designated as DENV 1 - 4 groups, which are widely circulating in both urban and peri-urban environments -14.Yellow fever virus (YFV) is the cause of the clinically important disease of public health concern called yellow fever infection. It is found in all continents but of more public health importance in the African and American subcontinents. It causes large epidemics in Africa and America with high morbidity and mortality. The incidence in West Africa is about 50 cases per 100,000 population, indicating the high infectivity of the virus in the region compared to the incidence of five cases per 100,000 population in South America. Paradoxically, the mortality rate in South America is higher than that in Africa, likely due to some genetic variability .St. Louis encephalitis virus (SLEV), a mosquito-borne flavivirus, occurs in North, Central, and South America and is one of the most important arbovirus infections in North America. It accounts for approximately 35% - 60% of aseptic meningitis in all symptomatic cases in children , 15.Zika virus (ZIKV) is a mosquito-transmitted flavivirus, that was discovered in Uganda in 1947, which later caused outbreaks in Micronesia, French Polynesia, and South and Central America. It was first isolated in humans in 1952, with only sporadic cases reported in Africa and parts of Asia. Subsequently, from 2001 onward, many outbreaks of ZIKV infections were reported in many parts of the world. In 2016, the World Health Organization announced that ZIKV was an international emergency . To date3) Bunyavirales: Bunyaviruses have a wide range of zoonotic life cycles. Mosquitoes transmit some members, like CEV and LACV, and therefore, cycle between mosquitoes and small mammals . They ar4) Reoviridae: The clinically important member of this family is the Colorado tick fever virus (CTFV), which cycles among many species of rodents and Rocky Mountain wood ticks. Between 2002 to 2012, about 83 cases of CTFV infections were reported mainly from the western parts of the US and Canada .ParamyxovirusesMolecular BiologyThese are broad family members of Paramyxoviridae that infect humans and animals. The three clinically important genera that are known to cause neurological diseases are 1) Rubulavirus with the mumps virus as a neurotropic virus, 2) Morbillivirus with measles virus as clinically important species, and 3) Henipavirus with Nipah virus (NiV) and Hendra virus (HeV) as neurotropic members -20.The mumps virus is an enveloped, non-segmented, single-stranded RNA virus with pleomorphic structures containing an inner ribonucleoprotein core structure with two protein molecules, one of which serves as RNA-dependent RNA polymerase. Two surface glycoproteins are responsible for the neuraminidase, hemagglutination, and fusion properties of the mumps virus that facilitate adsorption of the virion to host cells and penetration of the genetic material into the cells , 19, 21.The measles virus is a single-stranded, negative-sense RNA virus enclosed within a lipid capsule. It has a non-segmented genome of about 16,000 nucleotides linearly with six genes that encode eight viral proteins . The six structural proteins are haemagglutinin protein, fusion protein, nucleocapsid protein, phosphoprotein, matrix protein, and large protein. It is spherical with a diameter of about 100 - 200 nm and shows pleomorphism .Henipaviruses, including both NiV and HeV, are enveloped, single-stranded, nonsegmental, and negative-sense RNA viruses that represent emerging zoonotic infections that present with acute encephalitis and respiratory distress syndrome -23.EpidemiologyThe mumps virus (MuV) is a species of the genus Orthorubulavirus of the family Paramyxovirus affecting the CNS and glands. It is isolated in the saliva, cerebrospinal fluid, blood, breast milk, infected tissues, and urine. Transmission is through contact with respiratory secretions, saliva, direct contact, or through fomites, like bedding or doorknobs. It causes high cases of encephalitis in unvaccinated infants , 24. CasMeasles virus (MV), a member of the genus Morbillivirus, remained a leading cause of morbidity and mortality in the developing world, with an estimated 122,000 deaths in 2012. MV infection can cause severe debilitating CNS complications. It has been suggested up to 30% of cases with approximately 1:6,000 cases are complicated by more severe MV encephalitis. Transmission is via airborne droplets or small-particle aerosols that remain suspended in the air, direct contact with infected secretions, and less commonly, contact with contaminated fomites [Henipaviridae consists of two important viruses, the Nipah virus (NiV) and Hendra virus (HeV). The natural reservoir of both viruses is Pteropid bats, which harbor the viruses but do not show clinical illness. Virus transmission from bats to domestic animals is thought to be through pasture or feed contaminated by bat urine, feces, or other excretions. Transmission of HeV to humans has been invariably associated with close contact with ill horses while transmission of NiV, as reported from Bangladesh, is mainly through date palm sap contaminated with bat secretions. Human-to-human transmission of NiV also occurs -28. Arenaviruses (lymphocytic choriomeningitis viruses)Molecular BiologyLymphocytic choriomeningitis virus (LCMV) belongs to the family Arenaviridae, and it is the only member of the family that causes diseases in humans. It is an enveloped, single-stranded RNA virus with the genome containing two segments, the small (S) and the large (L) segments. The virus produces one nucleocapsid protein and two glycoproteins. The S segment encodes the nucleocapsid protein (NP) and the glycoprotein precursor (GPC). The L segment encodes the viral RNA-dependent RNA polymerase (L) and the small zinc finger-like protein (Z). More than 30 strains have been isolated with some enzymatic activities of polymerase and transcriptase functions .EpidemiologyLCMV is a member of the Arenaviridae family, with its primary host being the house mouse (Mus musculus). However, it has also been detected in other rodent species, such as hamsters, rats, and guinea pigs. The greatest risk of transmission occurs in laboratory workers, pet owners, and individuals living under impoverished and non-hygienic circumstances . It is fHerpes family virusesMolecular BiologyMeningitis and encephalitis have been associated with HSV infection and commonly results in severe consequences with severe developmental impairment and disability . The memHerpes simplex virus type 1 (HSV-1): HSV-1 is an enveloped, large deoxyribonucleic acid (DNA) virus that typically infects at epithelial surfaces with the subsequent establishment of latent infection in the sensory neurons. The virus has a double-stranded DNA genome of about 152 kb with two unique regions (long of about 108 kb and short of about 13 kb), and large inverted repeats flank each with a large number of simple sequence repeats (SSRs), also known as variable number tandem repeats (VNTRs) or reiterations. About 84% of the HSV-1 genome consists of protein-coding regions, which contain about 60% of the total SSR loci -35.Herpes simplex virus type 2 (HSV-2): The HSV-2 is a linear double-stranded DNA virus of about 154 kb. The genome also contains two unique regions as in HSV-1, long and short, but is bounded by a pair of terminal repeat and internal inverted repeat elements and over 74 open reading frames .Varicella-zoster virus (VZV): Varicella-zoster virus (VZV), also known as human herpesvirus 3, is a double-stranded DNA virus that naturally infects humans, with no animal reservoir. Primary infection usually occurs during childhood which causes varicella (chickenpox), it then becomes latent in the spinal and cranial ganglia. When the cellular immunity to the virus goes down with advancing age or in immunocompromised individuals, it then becomes reactivated and causes zoster (shingles) -37. The Epstein-Barr virus (EBV): Epstein and Barr are names of physicians who discovered virus particles in cultured lymphoblasts from Burkitt’s lymphoma (BL) in 1964 . It is oCytomegalovirus (CMV): Human CMV, a member of the herpesvirus group, is a double-stranded, linear DNA virus. The nucleic acid and the protein helically form a core covered by a protein capsid containing about 162 capsomeres, the majority of which are hexagonal in structure with a few pentameric. The diameter of the capsid is about 100 nm which is surrounded by a tegument, and when enclosed by a lipid bilayer envelope (which contains peplomers), the diameter reaches 180 nm. The length of the virion is about 230 - 240 kb .EpidemiologyChildren and immunocompromised individuals are the most vulnerable of herpes simplex meningoencephalitis. In the US, about 1,500 cases of HSV infection occur annually. The mortality rate of neonatal HSV infection, which is commonly contracted during delivery, can be as high as 80%, if left untreated, with serious neurologic complications -43. In tVaricella-zoster virus (VZV) has a worldwide distribution but more endemic in temperate countries. It is highly contagious in an overcrowded area, and transmission is via airborne droplet and contact with infected skin, the most common mode of transmission in children. The incidence is highest in preschool children aged one to four years with the distribution determined by seasonal variation, commoner during the winter and spring, and environmental conditions. Congenital VZV infections were reported in about 2% of infected pregnant women -37.Epstein-Barr virus (EBV) was identified in 1964 using an electron microscope from the cultures of African Burkitt lymphoma cells . It is dCMV is highly endemic in most of the world, and the distribution has no seasonal variation. The seroprevalence was estimated to be between 30% - 100% in a different part of the world. The seroprevalence in China is about 0.6% - 8.5% in the newborn and 58% - 84% in infants -48. The This review provided a current understanding of the molecular, epidemiologic, and biologic characteristics of some neurotropic viruses. The morbidity and mortality data of many viruses are provided herein. Various factors responsible for the spread and outbreaks of some viruses are also outlined. Moreover, the mode of viral transmission from the animal reservoir to humans has been explained. This should help the scientific community to better understand the different viral genomes and, therefore, to develop therapeutics and interventional measures. The study has some limitations, as only published data were used and was restricted only to molecular biology and epidemiology with no discussion on the neuropathogenesis. Further studies are required for exploring the relationship between disease causation and viral structure and the role played by the ecological, demographic, and environmental factors in the process.


Aims: To develop infectious (live/dead) enveloped virus test indicators and response surface methodology (RSM) models that evaluate survival of an enveloped ribonucleic acid (RNA) virus on contaminated aircraft materials after exposure to hot, humid air (HHA).Methods and Results: Enveloped RNA bacteriophage Phi6 (Φ6) was dried on wiring insulation, aircraft performance coating (APC), polypropylene, and nylon at ≥ 8 log10 plaque-forming units (PFU) test coupon−1. Only 2.4 log10 inactivation was measured on APC at 70°Celsius (°C), 5% relative humidity (RH) after 24 h. In contrast, HHA RSM models showed a 90% probability of a 7 log10 inactivation at ≥63°C, 90% RH after 1 h, and decontamination kinetics were similar across different materials. HHA decontamination of C-130 and C-17 aircraft showed >7 log10 and ≥5.9 log10 inactivation of enveloped virus on 100 and 110 test indicators, respectively, with a 1-h treatment, excluding ramp-up and ramp-down times.Conclusions: Enveloped RNA virus test indicators were successfully developed, lab tested for HHA decontamination, analyzed for RSM, and field-tested in aircraft demonstrations.Significance and Impact of the Study: The utility of HHA decontamination was demonstrated after inactivating enveloped RNA virus on aircraft with a 1-h HHA treatment within aircraft temperature and RH limits. Bacillus spore decontamination , causal agent of halo blight of the common bean, Phaseolus vulgaris, were isolated in Spain. Both were a kind gift from Dr. Leonard Mindich at Rutgers University, New Jersey Medical School. HB10Y was prepared by inoculating 100–200 ml of 3% tryptic soy broth  in a 1-liter (l) smooth-bottom Erlenmeyer flask with a high efficiency particulate air filter cap. Cultures were incubated at 26 ± 2°C, 200 revolutions (rev) minute (min)−1 for 20 ± 2 hours (h). 11.1 ml of 100% glycerol (Sigma PN #G7757-500ML) was added per 100 ml of host culture. The final concentration of glycerol was 10%. One-ml aliquots of HB10Y were pipetted into screw-cap microfuge tubes with O-rings and stored at −80°C. HB10Y samples were titered prior to freezing by serially diluting samples in 10 millimolar (mM) of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid  + 10% Sucrose (Sigma PN #S7903-250G), pH 7.0, and plating on Tryptic Soy Agar . Plates were inverted and incubated at 26 ± 2°C for 48 ± 2 h to show titers of ~109 cells ml−1. After freezing, tubes were thawed at room temperature , serially diluted, and plated to show sustained viability after long-term storage at −80°C.Φ6 and its host organism −1 overnight. Cells were then diluted and grown to mid-log phase. The host flask was inoculated with 0.5–1 ml of Φ6 at a concentration of ~1-2e11 plaque-forming units (PFU) ml−1 at the time of inoculation. The culture was incubated at 26 ± 2°C, 200 rev min−1 for 24 ± 2 h. The Φ6 preparation was stored at 4°C until after titering was completed. After titer determination was completed, typically around 1-2e11 PFU ml−1, then 1–1.3 ml volumes were aliquoted into 1.5-ml screw-cap tubes with O-rings, inverted, and stored at −80°C.Φ6 was prepared after inoculating broth cultures of HB10Y. A frozen stock prep of HB10Y was thawed at 22 ± 3°C. HB10Y was added either directly from a frozen stock or by transferring a single colony from a streaked TSA plate to 100–200 ml of 3% TSB in a 1-l smooth-bottom Erlenmeyer flask with a HEPA cap and incubated at 26 ± 2°C, 200 rev minThermotron SM-8-8200  environmental chambers were used to control temperature and RH as described  × 2 cm coupons of different test materials or the inside surface of 50-ml Techno Plastic Products AG, Switzerland (TPP®), polypropylene conical tubes were inoculated with >8 logRSM was used for previous work with HHA decontamination of materials contaminated with spores because the RSM Design of Experiments (DOE) was requested by the funding agencies as an industry-accepted method to describe HHA points of failure . A SF is simply the surviving population divided by the initial population. SF is assumed to never be greater than one or less than zero.The smallest non-zero SF that may be observed is limited due to the initial population being a finite number. Specifically, the smallest observable SF is 1 divided by the initial population. However, if the results reflect that of a 1-ml sample taken from a 10-ml sample (as is true for this data), then the smallest observable SF is 10 divided by the initial population. If extraction efficiency is <100%, then the smallest observable SF becomes 10 divided by the initial population divided by the extraction efficiency. If test data shows a surviving population of zero, it is likely because the theoretical SF is smaller than the smallest observable SF. Because of the limitation imposed by a finite initial population, any test result showing a survival population of zero was treated as a SF that is less than or equal to the smallest observable SF.The geometric mean survival fraction (GMSF) equation below shows how GMSF was calculated for each DOE point. In Equation 1, “N” represents the number of samples for a given DOE point.All GMSF values from the experiments lie between “0” and “1,” and they differ from each other by orders of magnitude, which can make it difficult to find a good fit to the data. To avoid this problem and to facilitate the data fitting process, it is desirable to transform the widely varying GMSF values such that the transformed values are distributed in a linear fashion. To achieve this, the natural log of the GMSF values was computed. However, this transform still resulted in a very non-linear distribution. A second transform was performed, using Equation 2 below, that flipped the sign of the first transform and then took its natural log. This yielded a more linear distribution of data.One benefit of this transform is that it constrains all model predictions to a value between “0” and “1” and thereby prevents a result that contradicts the definition of SF. Data fit exploration focused on obtaining a good fit to the data set of transformed GMSF values. During the data fitting process, a constraint was imposed on the fit such that as temperature and/or RH and/or time increase, SF decreases consistently without exception. The final functional form for predicting GMSF is shown in the system of equations below (Equation 3).Where:T = temperature (°C), R = relative humidity (%), H = time (hours)c0to c7 = addition and multiplication coefficientsn1to n3 = power coefficientsT0 = temperature offset coefficientR0 = relative humidity offset coefficientH0 = time offset coefficientGMSF = geometric mean survival fraction.10 kill with a 95% probability.As is evident in the data, a given exposure condition will result in a distribution of various SF values that can vary geometrically. Because of this geometric variation, it is appropriate to assume the natural log of the survival fractions for a given sample follow a normal distribution for a given exposure condition. An estimate of the expected distribution of results is important because it helps a user identify a probability that an expected total kill will occur for a given exposure condition. For example, a user can utilize the expected distribution to identify the exposure condition required to achieve at least a 7 logMost of the exposure DOE points consist of only 5 samples, and this small sample size increases the uncertainty in determining the population geometric standard deviation (GSD) from the sample geometric standard deviation. There was no clear and consistent pattern in the sample geometric standard deviations that would allow for the development of a reasonable equation to predict geometric standard deviation as a function of exposure conditions. However, the DOE center point  consists of 25 samples for each medium and consists of enough data to reasonably estimate a geometric standard deviation that is assumed to be representative for the entire DOE factor space. Using the test results from the DOE center point for each medium, the geometric standard deviation was computed using Equation 4 below.Where:n = number of samplesi = indexed reference to a particular sampleSFi = survival fraction for sample “i”GMSF = geometric mean survival fractionGSD = geometric standard deviation.The normal distribution of possible Survival Fraction logs for a given exposure condition is described by the natural log of the GMSF predicted using Equation 3 and the natural log of the GSD computed using Equation 4. The GMSF will vary based on exposure conditions and medium, but the GSD will only vary by medium. The equations for the Normal distribution are provided in Equations 5 and 6 below.Where:PDF = probability distribution function. Characterizes the relative frequency of occurrence.CDF = cumulative distribution function. The integral of the PDF with results ranging from 0 to 1.x = horizontal axis of possible Survival Fractionsnatural log of geometric mean survival fraction (GMSF)μ = natural log of geometric standard deviation (GSD)σ = erf = the error function.The cumulative distribution function equation returns the area for a region under the Probability Distribution Function curve by integrating from -∞ to a specified SF. A CDF result of “0.95” indicates that 95% of the SF values observed will be less than the specified SF.The Solver add-in for Microsoft Excel 2016 was used to explore various fits to the transformed survival fractions. The Solver add-in has the added benefit of allowing fit constraints which was crucial to obtaining a good and reasonable fit. The “Evolutionary” method in Solver proved a valuable tool in optimizing the coefficients shown in Equation 3. Excel was also used to produce the various plots in this report and assess model performance.10 coupon−1, and the test coupons were placed inside TPP® tubes prior to storage, shipping, and testing. Test indicators were placed in 20–22 locations with 5 test indicators per location within the aircraft. Each of the 5 test indicators was inoculated with an independent virus preparation. HHA tests were conducted inside a C-130 fuselage located at Army Combat Capabilities Developmental Command, Edgewood, MD, USA . These data drove the test parameters shown in In order to develop RSM performance envelopes, partial inactivation data was needed especially at the DOE mid-point. A small test at 50, 60, 70, and 80°C, RH at 5 or 90% for 1 and 24 h, produced critical data showing that high RH was critical for enveloped virus inactivation . The vir10 at 60°C, 90%, for 9 h. This surpassed the original goal of ≥7 log10 at ≤ 60°C, 24 h. Furthermore, the enveloped virus inoculum held in aqueous solution (solution controls) was shown to be much more sensitive to the rise in temperature than virus dried on to materials and subjected to hot, humid air. Therefore, water and/or high humidity were significant parameters for inactivating enveloped virus.Overall, there were several thousand trial-and-error data points leading to the HHA decontamination DOE data set in There was one statistical outlier for APC at 60°C, 50% RH for 5 h . The sub10 virus inactivation at 65°C, 90% RH, after virus-contaminated materials were treated with HHA.RSM for each material  were con10 objective and the 4 log10 inactivation parameters in the RSM composite model  the level of virus drying/level of free water was an important consideration for standardizing these tests and ≥24 h drying mitigated drying variability and (2) ≥24 h drying was done in attempt to mimic environments where free water is limited, especially for virus bound in debris. There was no Φ6 inactivation after the virus was dried on different surfaces for at least 24 h at RT followed by a 10-d exposure to 26.7°C at 80% RH, and there was only 2.4 logn et al. , Rabenaun et al. , and Chan et al.  tested sn et al.  and alsoThere is general agreement in the literature that higher temperature and humidity will increase the inactivation rates for enveloped virus. However, a direct side-by-side study would eliminate the impact of methods to define temperature and humidity profiles. This would also highlight physiochemical similarities/differences inherent to a specific virus or common to virus families  were frequently redefined by end users (aircraft maintenance authorities at Aircraft Mobility Command) over the past 20 years, and numerous goal changes were directed during the COVID-19 pandemic. The original goals were to show enveloped virus inactivation of ≥7 logThere were originally no time limitations set for aircraft sterilization (spore decontamination). The HHA time goal was reduced to ≤ 24 h for enveloped virus to increase HHA throughput and user acceptance. The time goal was further reduced by the end users and funding agencies to “1 h hold time; <6 h total time” after the COVID-19 pandemic had begun.The HHA temperature goal was originally capped at the accepted temperature limit of C-130 aircraft (80°C), but that was for sterilization (spore decontamination). The HHA temperature goal was reduced to 60°C for the enveloped virus to increase HHA acceptance over a range of aircraft since 60°C is a standard, accepted test temperature for most aircraft materials. The time goal of ≤ 24 h provided the rationale for measuring HHA over several hours to develop RSM models. However, the end users and funding agencies raised the accepted temperature limit to 68.3°C during COVID-19 to reduce decontamination time.Although there was a strong preference to reduce/eliminate humidity from HHA to reduce cost and complexity, all of the experimental data here showed that Φ6 was stable after drying. Virus was quickly inactivated after it was diluted in aqueous solutions and heated (solution control data). For HHA, the combination of high heat and high humidity, i.e., a high dew point, was critical to virus inactivation on materials in hour-long timeframes. This is consistent with long-known observations that enveloped virus is stabilized after drying on fomites. As an example, the enveloped virus smallpox was stabilized after it peeled/sloughed along with host cells and then dried on porous materials including clothes and blankets. Furthermore, historic data shows that enveloped viruses were stabilized in cold, dry climates Fenn, .10 enveloped virus inactivation after both aircraft field tests, as predicted. The RSM models were also used as a guide for a number of iterative improvements between the first and second aircraft demonstration that shortened the overall HHA decontamination time from 5.5 to <3.5 h.The end goal of the RSM was simplistic graphs where all decontamination test variables could be compared, understood, and utilized for field testing and field application. This was particularly useful for large hot, humid air decontamination systems with fluctuating temperature and RH, potential power disruptions, and decontamination goals that have fluctuated widely over time. Since the RSM models showed little difference in inactivation kinetics among the different materials, a composite RSM was developed as a primary reference guide. This reference guide served the purpose of guiding HHA field testing in aircraft. The RSM models translated to field demonstrations because there was a ≥5.9 logThere were numerous conclusions. The Φ6 test indicators were useful measurements of inactivation for both lab and field testing. HHA successfully inactivated enveloped virus at high temperature and high humidity. The RSM models were adaptable to changes in user requirements and successfully utilized to predict HHA results for field applications. Much methods development and testing remains to confirm HHA inactivation kinetics across virus species, and to develop HHA models that include HHA ramp-up and ramp-down times. Lastly, HHA decontamination of aircraft was successful because the enveloped virus on the C-17 aircraft was inactivated, the aircraft was flown after the HHA field test, and then the C-17 was certified as an operational aircraft.All datasets generated for this study are included in the article/supplementary material.TB was the principal investigator and the principal for methods development, test design, execution analysis, and writing. AY was a lead tester and contributed to methods development test design, execution, and data assembly. EB-K, NK, ZM, MBo, and EO participated in methods development, test design, test execution, and data assembly. SH, MK, MH, CM, RM, JI, MBe, BG, VY, SL, EH, and BL contributed to test execution and data assembly. HB was the math modeler. All team members participated or contributed to writing, figures, tables, and/or editing.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


The potential financial burden of American football-related concussions (FRC) is unknown. Our objective was to describe the healthcare costs associated with an FRC and determine factors associated with increased costs.A retrospective cohort study of concussed high school football players presenting between November 2017 and March 2020 was undertaken; 144 male high school football players were included. Total costs were about $115,000, for an average direct healthcare cost of $800.10/concussion. Visiting the emergency department , the initial post-concussion symptom scale score  and a post-concussion syndrome diagnosis  were each independently associated with total costs.A granular understanding of cost-driving factors associated with FRC is the first step in understanding the cost–effectiveness of prevention and treatment methods. The healthcare costs, or the costs incurred by the healthcare system, associated with a single concussion in American high school football are unknown. We reviewed the records of 144 high school football players who received concussion care at our sport concussion center and calculated the direct healthcare costs associated with the appointments, imaging studies and therapies received, when applicable. We found that each concussion results in about $800 of healthcare system spending. A few factors were associated with greater costs, including visiting the emergency department and having symptoms for over 1 month. Furthermore, the more symptoms an athlete had at their first clinic visit, the higher total cost of care. Understanding these costs can potentially help clinicians and researchers determine the best ways to maximize care while minimizing the costs. A sport-related concussion (SRC) is a mild traumatic brain injury (mTBI) sustained during sports, which is clinically diagnosed and associated with negative standard head imaging, when performed . Nearly While SRC costs will likely vary as treatment evolves ,9, a fisGiven the high incidence of football-related concussion (FRC), a granular understanding of the healthcare costs associated with FRC is the first step to ensuring equal prevention and treatment practices for all. The objectives of the present study are to: describe the healthcare costs associated with an FRC, and determine what clinical factors are most associated with increased costs. We hypothesized the development of post-concussion syndrome (PCS) would be particularly associated with higher costs.A retrospective cohort study was undertaken between November 2017 and March 2020 for concussed American high school football players. All patients were evaluated and received the majority of their FRC care at a sport concussion center located in the Southeast United States. The study was determined exempt by the Institutional Review Board (IRB #192033) based on minimal risk designation (45 CFR 46.104(d)(4)) and the need for patient consent was waived accordingly following IRB review.All patients seen at the regional sport concussion center during the study period with visit-associated ICD-10 billing codes for concussion  were queried. Patient selection is summarized, and exclusion criteria are detailed in Relevant pre-injury clinical variables, including demographics and medical/family history as well as injury characteristics  were chosen based on published literature demonstrating importance of these variables in predicting prolonged recovery . InitialThe dates of each concussion-related healthcare system contact were collected. Time (days) from injury to initial evaluation by each type of healthcare provider, as well as the number of visits to each type of provider, were calculated. Emergency department (ED) and urgent care visits were collapsed into a single variable due to an overall low count of urgent care visits and the two provide a similar service involving the initial assessment and diagnosis of SRC. Imaging was identified by radiology reports and imaging studies were verified to be SRC-related by reviewing temporally associated provider notes. The presence of outside facility imaging studies, urgent care or ED use was determined by close review of the initial concussion clinic consultation note, as these variables are systematically documented as part of our institution's initial clinic evaluation.a-priori as end points. Return-to-learn: days from injury to return to school (part or full time); return-to-play: days from injury to full clearance for return to practice and/or games; symptom resolution: days from injury to when PCSS was 0 or the treating clinician stated the athlete had ‘recovered’ from his concussion; and PCS: whether or not the athlete developed PCS, defined as >1 symptom continuing over 1 month (28 days) post-injury [A concussion episode was defined as time from initial injury to discharge from the clinic, which typically occurred when the athlete was cleared for return to play or became asymptomatic as athletes typically return to school prior to discharge from clinic. Four clinical outcomes, including three time-to-recovery variables, were chosen t-injury . If an aThe direct cost of the concussion episode was the primary outcome. Each patient's cost data was derived by matching visit and imaging dates with study institution inflation-adjusted cost data. Notably, costs were used instead of charges, which can fluctuate greatly by region/hospital ,23. CostDescriptive statistics were performed, with continuous variables represented as median with IQR and categorical variables as N (%). Sample size was determined by the number of available records, and thus no sample size or power calculation was performed. Missing data were imputed using mean value imputation. Three patients – two with non-contrasted head CTs (CTH), one with a cervical spine (c-spine) MRI – underwent in-system imaging related to their concussions, for which cost data were missing, and these costs were imputed by averaging inflation-adjusted costs for CTH and c-spine MRI collected from other patients. For patients receiving outside imaging and/or outside ED care, the costs were imputed utilizing the mean in-system cost of these services. Wilcoxon rank-sum tests were used to compare the initial symptom burden and total costs incurred by those who did and did not develop PCS given non-normally distributed data.2) was included in the regression model.A multivariable linear regression model identified clinical factors associated with the total cost of concussion care. In-system ED visits were included as a covariate to mitigate the confounding influence of this variable. Based on the anticipated relationship between PCSS and cost, a nonlinear quadratic term for this variable .The threshold for statistical significance was set Demographics, clinical characteristics and outcomes of the 144 concussed high school football players are presented in Complete healthcare system utilization and costs per concussion and costs per resource utilization are presented in Multivariable linear regression revealed that presenting to any ED or urgent care was independently associated with total cost . Additionally, there was a statistically significant association between the squared PCSS and total cost , indicating a quadratic relationship . AccordiWe sought to determine the average direct cost to the healthcare system of an FRC among US high school athletes. Over $115,000 was spent across 144 football SRCs for an average cost of $800 per concussion. Our initial hypothesis was supported, as a diagnosis of PCS was independently associated with higher costs and athletes. Additionally, we found that both visiting the ED and a higher initial symptom burden were independently associated with increased costs. These results represent one initial attempt to quantify the direct costs of SRC, and describe the relationship between symptom burden, prolonged recovery and direct healthcare costs for male, high school athletes who suffer a concussion playing football.et al. [et al. [Many investigations have quantified costs associated with mTBI ,8,26,27.et al. . This diet al. . Further [et al. ,12,30.Emergency room evaluation was independently associated with a higher cost per concussion episode. The indication for an ED visit was not standardized nor documented, but red flags symptoms  may have been present, warranting the visit. Improving the efficiency of ED utilization represents a potential method to reduce costs. For example, limiting CTH to evidence-based indications , improviInitial symptom burden was strongly associated with costs. Though initial symptom score has been associated with protracted recovery ,30, to oOver the last decade, helmet research has shifted toward concussion prevention and risk reduction . DespiteConsider the hypothetical $525 upgrade from the Riddell Speedflex MSRP $425 ) to the 5  to theThe primary strength of this study is providing an initial attempt to provide a granular accounting of the direct costs associated with FRC. Compared with other ‘cost’ studies, a major strength of this study lies in the use of hospital cost data rather than billing charges or reimbursement. Charges can greatly overestimate direct costs and cannot be compared across multiple hospital systems while reimbursement can similarly change due to insurer, hospital market share and an individual's ability to pay ,23,46. TDespite these strengths, there are important limitations to this study in addition to regional care differences that may limit generalizability. First, direct costs of concussion care reflect those incurred by the health system and these results do not account for costs attributable to FRC that occur outside our health system. Imputed imaging and ED costs mitigate this limitation and inclusion criteria were deliberately set to include athletes who would have received the vast majority of their care within our hospital system. Second, we decided to focus on direct costs rather than providing estimates of indirect costs. Specifically, we did not include the costs of health-related quality-of-life (HRQOL) detriments due inconsistent effect of sports-related concussion on HRQOL among studies ranging from no difference  to substSimilarly, our study reflects the relatively acute or initial costs associated with FRC. There is emerging evidence of psychological maladies associated with FRC that may lead to higher longitudinal healthcare costs ,53. Yet,Finally, we focused on a single sport for this initial investigation given the high incidence of FRC and the expenses associated with injury prevention specific to this sport. Future investigations can expand to understand differential healthcare utilization across sports and decision-tree analyses may determine the cost-effectiveness of rehabilitation-based versus equipment-based interventions.The average cost of a concussion suffered playing high school American Football in the Southeastern USA is approximately $800. Costs are independently associated with the initial symptom burden, ED utilization and/or development of PCS. A granular understanding of the costs and cost-driving factors associated with concussions is a critical first step to study the cost–effectiveness of prevention and treatment methods. We encourage further investigations of the cost–effectiveness of SRC-related interventions in order to make sound economic and scientifically based decisions.As the prevention and treatment of SRC continues to advance technologically and scientifically, the potential costs to athletes, teams, society and the healthcare system have the potential to expand indefinitely. As these costs mount, attention must be placed on the costs per unit benefit. Stakeholders will demand that these rising costs are matched with benefits in the form of markedly reduced recovery time, reduced risk of any long-term effects of SRC or improved primary protection from SRC. Simple advances that achieve meaningful improvements with near negligible costs will be preferred to significant technological advancements accompanied by disproportionate costs that yield only minor improvements over existing products, methods and treatment standards.American high school football-related concussions (FRC) are exceedingly common.The healthcare costs of these injuries and what factors drive greater costs have not been previously described.A total of 144 American high school football players who suffered an FRC were included.All players received care through a regional, multidisciplinary concussion clinic.The direct healthcare cost per concussion was about $800.These costs reflect the direct cost of care to the healthcare system, providing an objective cost measure.These costs are objective, reproducible and more generalizable to other health systems, unlike costs/charges as assessed by the insurance company or experienced by patients as these others costs/charges are highly variable across carriers and patients.Visiting the emergency department, higher initial symptom burden and developing post-concussion syndrome each independently drove higher healthcare costs.This provides a calculation of the direct healthcare costs of a sport-related concussion (SRC) in any sport as well as demonstrates the association between symptom burden and costs for the first time.Understanding the costs associated with SRC provides the groundwork for demonstrating cost-effectiveness of interventions – both preventative and treatment – in the future.


The durability of natural and treated clay soil stabilized with lime and alkaline activation (AA) affected by environmental factors (hot and humid) was determined in this study. Investigation and evaluation on the strength of the soil, moisture content, and volume change of the specimen were determined at each curing period  based on the weather conditions. An unconfined compressive strength (UCS) of the specimen at three different wetting/drying cycles  was determined. The findings show that the strength of the treated specimens fluctuated with increment and decrement strength (one and three cycles) in the range of 1.41 to 1.88 MPa (lime) and 2.64 to 8.29 MPa (AA), while for five cycles with a curing period of 90 days the decrement was in the range of 1.62 to 1.25 MPa and 6.06 to 5.89 MPa for lime and AA, respectively. The decrement percentage for treated samples that were subjected to five cycles of wetting and drying in 90 days was found to be 20.38% (lime) and 38.64% (AA), respectively. Therefore, it can be summarized that wetting/drying cycles have a significant influence on the durability, strength, and the volume changes of the specimens. Marine clays are natural sediments that originate from coastal areas under saline environmental conditions . They teStabilization using lime is one of the common techniques in improving the earthworks as its usage is continuous since its introduction in the past century. The modification using lime has been widely used due to the rapid effectiveness in subgrade soft soil and building embankment that changes the geotechnical characteristic, such as the soil compaction, shear strength, and plastic limit. Past researches ,6 have pFly ash (FA) is one of the binders used for stabilization and is a waste by-product that has been used as precursors in an alkaline activation (AA). The utilization of fly ash as admixture or filler material is more conducive as it is not only a more sustainable and environmentally friendly waste material, but it can also be promoted for land conservation purposes. There are many benefits of FA as a precursor of soil treatment, such as exhibiting higher mechanical strength, more ductility, and a decrease in the collapsible potential of the soil ,8,9. HenNevertheless, ,11 notedFiber can be classified into two types that are either natural fiber or synthetic fiber where each type of fiber has its own specialty that differs from others. Coir fiber is a type of natural fiber. The selection of coir fiber is also due to the awareness that it has an environmentally friendly and sustainable life. Other than that, the usage of coir fiber as a reinforcement gains interest in research studies due to its advantages such as being abundantly available, of low cost, a renewable resource, lightweight, and having good mechanical properties compared to other natural fibers ,20,21,22Therefore, this research attempts to study the effectiveness of the durability test for the treated soil (lime and AA) with the inclusion of fiber subjected to wetting drying cycle tests. The changes on strength and physical properties for the both treated clay soils were examined by conducting the unconfined compressive strength test (UCS). For the microstructural changes, scanning of electron microscopy analyses (FESEM) and Energy Dispersion X-ray (EDX) were performed to explain the reaction and strength of the clay soil development.The soil used in this study is a clay soil collected from a coastal area in Klang, Selangor. The physical properties of the marine clay were tested in accordance to BS 1377-2-1990 [Coir fiber used in this study was obtained from a factory at Batu Pahat, Johor. A total of 1% fiber was selected as the most effective percentage for soil reinforcement to improve the ductile behavior of the treated soil as suggested by . Researc2) was used in this study as a binder for the stabilized soil. The chemical was supplied by Evergreen Engineering, which has a chemical content of (lime) more than 90% applicable for this study. A total of 5% of lime was used as stabilizer, which is considered to have a positive effect as lime fixation point and particularly succeeds in generating maximum strength for the workability of the soil [Hydrated lime (Ca(OH)the soil ,44.2, Al2O3, and Fe2O3 as demonstrated in Fly ash (FA) is a material that originates from a bituminous power plant coal combustion obtained from a local factory near Selangor. The type of FA used in this study was class F type, which was classified as having low calcium content ASTM C 618 . The cum+ cation was selected as the alkaline activator that is suitable in mixing with fly ash. Generally, the selection of a suitable concentration for the activators is between 4.5 and 18 molar [Activators play an important role in the development of soil strength. In this study, potassium hydroxide (KOH) containing K18 molar ,47. Mola18 molar . Pourakb18 molar  also sta18 molar .The collected soil sample was dried in an oven at a temperature of 105 °C for 24 h before being crushed and sieved passing through a 2 mm sieve. In this study, four types of main material were used, which are soil, hydrated lime, fly ash, and coir fiber. All of the specimens were prepared by using a hand mixer. As for soil stabilized with lime, 5% of hydrated lime  and 1% of treated fiber  were used in order to increase the strength of soil (Anggraini ). For AAThe evaluation strength of untreated and treated clay soil specimens was determined by using an unconfined compression test. The specimen was tested according to BS1377-7-1990 . Each saThe wetting/drying cycles conducted in this study were in accordance with the ASTM D 599 ,53,54,55qu) of the soil specimen at each cycle  towards the peak compressive strength (qu) of the specimen at the none number of the cycle (without wetting/drying cycles) at different curing periods.In this section, the determination of the durability index, dry density (ρd), moisture content (MC), and weight loss is for the untreated clay and treated clay with lime and alkaline activation, according to  and BS 1The dry density of the soil is determined as the mass of the dry soil contained in the unit volume of the undried materials where the calculation is based on Equation (1) below .(1)ρd=.Next, the parameter of the weight of soil loss is expressed as the initial dry unit of treated soil specimens after being subjected to wetting/drying cycles over the untreated soil specimens .The FESEM and EDX analyses were conducted to analyze the morphology on the soil surface and the element composition of the untreated and treated soil specimen using the dispersive X-ray spectrometer The dry specimen was mounted on the platinum sample with adhesive carbon tape before being sputter-coated using the Q150R S Sputter coater . The sputter coater is used to improve the surface electrical conductivity and thus reduces the charging effect. The micrographs of the specimen were obtained and reviewed under SU 8010 FESEM .The relationship between the compressive stress versus compressive strain of the untreated clay and treated clay with lime and AA subjected to wetting/drying cycles after 7, 28, and 90 curing days is presented in Next, the wetting/drying cycles have a large effect on the increment of strength for the lime treated sample (for one and three cycles) in the range of 1.41 to 1.88 MPa and 2.64 to 8.29 MPa. While for the five cycles c of a peIn addition, the soil stabilized with AA reached the highest approximate dry state compared to the lime-stabilized soil. The high dry state of the specimen is due to the tendency of the stabilizer to fill the pores between the soil particles, thus sealing the voids and presenting water to infiltrate into the soil. Furthermore, based on Other than that, the wetting/drying cycles show an increase in compressive strength after the first three cycles for 7, 28, and 90 days of treated soil and start to decrease at five cycles only at 90 days of the curing period. The increase of the compressive strength on the curing period as well as the cycles might be due to the low absorption of water towards the soil specimen. In addition, the strength increment of the soil specimen is likely to show a high maturity of the curing period for the specimen where in this case, the specimen able to withstand the effect of the wetting/drying as the soil particles start to strengthen together. The deterioration of the strength for the treated soil after three cycles (for 90 days) might be due to the bond and the interlocking between the soil particles becoming loose.However, the reduction on the strength from the third cycle onward is observed as not being too significant. Not to mention that the particles in the specimens are going through disruption which then causes the changes of the structure in the particles. The authors of  show simFor a better understanding regarding the effect of the wetting/drying cycles to the strength performance of the soil specimens, the durability index tests were performed on each of the stabilized soil specimens with lime and alkaline activation. It can be clearly seen that the dry density of the soil decreases slightly with the increase of wetting and drying cycles, and the water content increases with the increase of wetting/drying for all types of specimen, respectively. The decrement of the dry density is linked with the increase of the water content of the stabilized soil in which the percentage increase of the water content is in the range of range 2%–14%, increasing the cycle from the first cycle to the fifth cycle. The condition of increment of the water content on the stabilized soil is probably due to the fiber inclusion that helps in absorbing the water content in the soil at low dry density. Although there is a high water content in the soil with the increase of the curing period and wetting/drying cycles, the ability of fiber inclusion to help in retaining the water content while the stabilizer helps in reducing the dry density of the soil gives a good advantage in strengthening the soil. As for decreasing and increasing the dry density and water content for lime stabilization, inclusion of fiber in the soil matrix has helped in improving the water absorption rate, thus strengthening the soil properties. This statement has similar findings with past researchers ,48,58,59Moreover, the increase of the water content for the soil specimen was believed to be due to the pozzolanic reaction that started to occur between the stabilizer and the activator. The process of wetting/drying of the specimen was disturbed as the sample started to react with the chemical. The percentage of water content and weight soil loss of the three curing periods of 7, 28, and 90 days for the lime and AA increase simultaneously in line with the increase in wetting and drying cycles, as can be seen in the results for 2SO4 solution. Equation (3) below shows the cementitious reaction that occurs when there is a high amount of Al2O3, SiO2, Fe2O3, and CaO with addition of water.The percentage of weight loss for the soil stabilized with lime and AA versus the number of cycles is illustrated in The hydration process is constructed as for CaO (lime) liberates OH- ions, as shown in Equation (4), which contributes in increasing the pH value up to 12. The pozzolanic reactions which are rich of Ca with the combination of silica (Si), alumina (Al), and iron (Fe) resulting for the C-A-H and C-S-H gels for longer curing stages ,62 can bPozzolanic reactions:2+, SiO2, and Al2O3 in the specimens resulting from the lime and AA stabilizer the strength of the soil is increased. Furthermore, [−, Ca2+, AlO6, and SiO4.hermore, ,66 has mIn addition, the cementation pozzolanic reaction of Calcium Aluminate Hydrate (C-A-H) and Calcium Silicate Hydrate (C-S-H) can be proven from Equations (5) and (6) above, where high pozzolan rich of silica and alumina contributes to the formation of CAH and CSH. Therefore, the formation of the binder has proven to contribute to the increment of unconfined compressive strength of the modified clay with lime and AA compared to the untreated clay soil due to the interlocking arrangement that occurred between the soil particles.The effects of the wetting/drying test on the strength of the soil (for both stabilized lime and AA) for all different curing dates and cycles show a less significant fluctuation of increment and decrement except for a curing period of 90 days, where there is a sharp decrement that occurs at the first three cycles. This may be attributed to the effect of the wetting and drying that changes the formation of the soil occurring within the material with the increase of curing periods;The strength of treated soil with lime and AA started to decrease after a curing period of 28 days where the decrements were 13.19% and 38.64%, respectively, notable mostly at the fifth cycle. This is due to the interfacial bonding caused by a chemical reaction that occurred between the soil particles and the stabilizer being reduced, which resulted in loosening the soil particles as the cycle period increased. It is also due to the conditions where the specimens with dried conditions for a long-term duration were then exposed to a wetting/drying cycles, which tends to cause the soil to be in a moist condition, thus attributing to a decrease in soil strength;Dry density and water content versus cycles show a similar trend for both soils stabilized with lime and AA where decrement occurs for dry density and increment of the water content for all specimens, respectively. This may be due to the usage of the stabilizer and the fiber inclusion that helps in lowering the dry density of the soil and the ability of the stabilizer to absorb a large amount of water, as for lime and alkaline activation;An increasing trend of the soil percentage loss was observed with the increase of the wetting/drying cycles for both soil stabilization treatments with an accumulation of 3% to 5% increment, except for the first cycles of treatment with lime. This is due to the absorption of water into the soil voids that forms between the binders, thus leading to soil loss;Analysis of the FESEM and EDX results shows a dense and compacted soil with fewer visible pores after a curing period of 90 days. The admixtures help in filling the pores and strengthen the soil. From the EDX result, it is also confirmed that there is a formation of CSH and CAH  gels thaThe findings on the research of the effect of the environmental condition, which subsequently are referred to wetting/drying cycles, on the durability and strength of the stabilized soil with lime and alkaline activation, can be concluded as follows: