Severe and fatal vivax malaria is increasingly reported from India. In Mangaluru, southern India, malaria is focused in urban areas and associated with importation by migrant workers. In Wenlock Hospital, the largest governmental hospital, the clinical, parasitological and biochemical characteristics of malaria patients were assessed.During the peak malaria season in 2015 (June to December), outpatients were interviewed and clinically assessed. Malaria was ascertained by microscopy and PCR assays, concentrations of haemoglobin, creatinine and bilirubin, as well as thrombocyte count, were determined, and severe malaria was defined according to WHO criteria.Plasmodium vivax–Plasmodium falciparum infection (21.3%) and falciparum malaria (9.0%). The geometric mean parasite density was 3412/µL. As compared to vivax malaria, patients with falciparum malaria had higher parasite density and more frequently showed impaired general condition, affected consciousness and splenomegaly. Also, they tended to more commonly have anaemia and increased creatinine levels, and to be hospitalized (7.3%). Mixed-species infections largely assumed an interim position. Severe malaria (3.5%) was not associated with parasite species. No fatality occurred.Among 909 malaria patients, the vast majority was male (93%), adult  and of low socio-economic status. Roughly half of them were migrants from beyond the local Karnataka state, mostly from northern and northeastern states. Vivax malaria (69.6%) predominated over mixed P. falciparum causing slightly more intense manifestation. Severe malaria was infrequent and fatalities absent. This contrasts with the reported pattern of manifestation in other parts of India, which requires the analysis of underlying causes.In this study, uncomplicated cases of malaria predominated, with  Plasmodium vivax cases worldwide  was absent, the highest parasite density observed was 148,325/µL in a patient with mixed-species infection. Parasite species did not significantly affect the proportion of severe malaria, which occurred in 3.2% (20/633), 4.1% (8/194) and 4.9% (4/82) of cases with vivax malaria, mixed-species infection and falciparum malaria, respectively . Severe malaria was rare (3.5%), and fatalities absent. Overall, P. falciparum and mixed infections showed a more pronounced manifestation than vivax malaria although respective differences were moderate. This contrasts with the severity and associated deaths of P. vivax infections reported from other regions of India [In this study from the largest governmental hospital in urban Mangaluru, coastal southern India, almost 70% of malaria episodes were due to patients 6%. Severof India .The present study has several specifics and limitations, which need to be considered when interpreting the findings. Wenlock Hospital is largely attended by adult male patients of comparatively low SES, more than half of whom are construction site workers or daily labourers. This pattern in turn may impact on knowledge and awareness of malaria, degree and pace of health care utilization and thus on the clinical picture , 24, 25.P. falciparum mono-infection was significantly increased in construction workers and reduced in migrants from north/northeastern India, although both factors overlapped. In the latter region, the burden of malaria is increased as is the proportion of P. falciparum [P. falciparum-related semi-immunity as compared to the local Mangaluru population and consequently some degree of resistance to locally transmitted P. falciparum parasites. Alternative explanations include an increased relapse rates in imported P. vivax strains, poor compliance with the 2 weeks of primaquine treatment, or an increased rate of common infectious diseases among the economically deprived migrants giving rise to an increased P. vivax relapse rate [P. vivax.Interestingly, falciparum malaria appeared to be a local rather than an imported disease. The prevalence of lciparum . Conceivpse rate . In thesP. vivax infections was lowest whereas that of P. falciparum was highest. In India, both temperate and tropical types of P. vivax relapse  occur [P. vivax still predominated among the attending patients and P. falciparum proportionally increased with increasing precipitation and thus transmission.One month after the peak of precipitation, the proportion of y) occur  but for P. falciparum. Nevertheless, upon clinical examination, patients with falciparum malaria showed worse general and consciousness conditions than patients with P. vivax or mixed infections. This may be partly due to the increased parasite counts and reduced nutritional status observed in falciparum malaria patients. On the other hand, cytokine production, potentially affecting the general condition, is higher in P. vivax infection than that in P. falciparum infections of similar parasite numbers [P. falciparum as compared to P. vivax infections included the highest proportion of severe thrombocytopaenia as well as trends towards more frequently increased creatinine and bilirubin levels, more anaemia, and more common hospitalization. Altogether, these differences were modest. Mixed species infection largely assumed an interim position between the manifestations of P. vivax and P. falciparum. Notable exemptions were the highest proportions of anaemia and hypotension. Given the only minor differences in the clinical picture according to parasite species, the present study does not contribute to solving the question whether mixed-species infections do rather attenuate falciparum malaria or increase its severity [P. falciparum infections (34%) were more common than in the present study but mixed infections slightly less prevalent (14%). Data are not well comparable because of a considerably larger proportion of inpatients (61%) in that study but it is noteworthy that, similar to the present study, falciparum malaria was associated with increased rates of hospitalization and of altered consciousness. In the previous study from Mangaluru, two patients (1.1%) reportedly died due to cerebral malaria (no parasite species provided).Reported signs and symptoms did not differ substantially with parasite species even though gastrointestinal symptoms  appeared to be slightly increased in infections comprising  numbers , 30. Othseverity , 12, 31.severity  also repP. vivax infection is increasingly reported since the year 2000, and > 40% of respective studies originate from India whereas a large number of endemic countries do not report severe vivax malaria at all [P. vivax infection and a thrombocyte count of 78,000/µL. Other reasons for the heterogeneity of severe vivax malaria potentially include geographical differences in the peak age of vivax malaria, endemicity, chloroquine resistance, parasite virulence, and misdiagnosis of other severe diseases [P. vivax can cause severe and fatal disease, and the existing evidence has thoroughly been reviewed [Severe malaria due to a at all . The incdiseases . Beyond reviewed , 33. HowSevere malaria in the present study occurred at similar proportions irrespective of parasite species. Reported diabetes mellitus was its strongest independent predictor followed by female gender, thrombocytopaenia, and increasing age, while increasing BMI was protective. Increased susceptibility to malaria in diabetic individuals has been reported from Africa  and therMalaria in Mangaluru, coastal southern India, affects predominantly young men of low-socio-economic status, many of whom are migrant workers from other parts of India, and rarely causes hospitalization. Severe vivax malaria does occur in this setting at a rate only slightly lower than in falciparum malaria but its prevalence contrasts with substantially higher figures reported from elsewhere in the country. Studies into pathophysiology and parasite biology are needed to disentangle the respective heterogeneity.


Plasmodium infections that require more sensitive methods for accurate diagnosis and early treatment of malaria. This is particularly relevant in low-malaria transmission areas, where intermittent preventive treatment is not recommended. Molecular methods, such as polymerase chain reaction (PCR) are highly sensitive, but require sophisticated equipment and advanced training. Instead, loop mediated isothermal amplification (LAMP) provides an opportunity for molecular detection of malaria infections in remote endemic areas, outside a reference laboratory. The aim of the study is to evaluate the performance of LAMP for the screening of malaria in pregnant women in Colombia.Pregnant women frequently show low-density Plasmodium parasites by light microscopy (LM), rapid diagnostic test (RDT) and LAMP. Diagnostic accuracy endpoints  of LM, RDT and LAMP were compared with nested PCR (nPCR) as the reference standard.This is a nested prospective study that uses data and samples from a larger cross-sectional project conducted from May 2016 to January 2017 in three Colombian endemic areas . A total of 531 peripheral and placental samples from pregnant women self-presenting at local hospitals for antenatal care visits, at delivery or seeking medical care for suspected malaria were collected. Samples were analysed for p < 0.01), particularly in afebrile women, for which LAMP sensitivity was two-times higher than LM and RDT. Overall agreement among LAMP and nPCR was high . Specificity was similar in all tests (100%). In placental blood, LAMP evidenced a four-fold improvement in sensitivity (88.9%) when compared with LM and RDT (22.2%), being the only method, together with nPCR, able to detect placental infections in peripheral blood.In peripheral samples, LAMP showed an improved sensitivity (100.0%) when compared with LM 79.5% and RDT 76.9% (LAMP is a simple, rapid and accurate molecular tool for detecting gestational and placental malaria, being able to overcome the limited sensitivity of LM and RDT. These findings could guide maternal health programs in low-transmission settings to integrate LAMP in their surveillance systems for the active detection of low-density infections and asymptomatic malaria cases. Plasmodium infections and have the risk of developing severe disease and birth complications. These might include maternal anaemia, intra-uterine growth retardation, infant low birth weight, prematurity, miscarriage and stillbirth .When comparing the total number of P. falciparum .Regarding placental samples Table , LAMP idp < 0.01] and RDT . No statistically significant difference was observed between LM and RDT sensitivity. Specificity was similar in all tests [100.0% (95% CI 99.2–100.0)] ] when compared to LM  Table .Table 3PDiscrepant results between LAMP and nPCR were initially observed in six samples: three LAMP positive/PCR negative and three LAMP negative/PCR positive. Those samples were run in triplicate using nPCR and confirmed the original LAMP results.p < 0.01]. Among the 39 malaria positive cases detected by nPCR, the prevalence of febrile and afebrile infections was 59.0% (23/39) and 41.0% (16/39), respectively. The median parasite density in febrile infections was 3235 p/μL  and the proportion of low-density infections was 0% (0/23) while in afebrile infections the median parasite density was 1410 (range 140–3540) and the proportion of low-density infections was 52.9% (9/17).Considering test performance in febrile (50) and afebrile 437) pregnant women, all methods showed very similar results for detecting febrile infections (23/50). LM and LAMP displayed higher sensitivity [100.0% (CI 95% = 87.5–100.0)] than RDT [95.0% (CI 95% = 76.4–100.0)] ] when compared with LM and RDT [22.2% (CI 95% = 6.3–54.7)]. Specificity was similar in all tests [100% (95% CI 98.5–100.0)] , no infection was detected by LM or RDT. LAMP and nPCR detected five of the nine placental infections in peripheral blood identified by nPCR on placental blood samples (reference test in this case), translating in a sensitivity of 55.6% (95% CI 26.7–81.0) for both diagnostic techniques  [In the current study, the overall MiP positivity rate in peripheral blood confirmed by nPCR was lower (7.3%) than previous studies conducted in Colombia 14–32%) , 14, but–32% , 14l blood) , particul blood) .When using LAMP on peripheral samples, a significant improvement in sensitivity was observed as compared with LM and RDT , and overall agreement among LAMP and nPCR was high (kappa = 1.0). These results were consistent with previous studies proving higher performance of LAMP for the diagnosis of malaria in pregnant , 29 and Consequently and in light with these results, further studies are needed to evaluate the potential integration of LAMP into clinical and surveillance programs to promptly detect and effectively treat malaria infection in pregnant women attending ANC visits and at delivery. There is also a need to evaluate the costs per assay comparing to conventional test, including equipment, reagents, labour, training and maintenance in order to evaluating the cost-effectiveness of LAMP for their potential integration into clinical and surveillance programmes.P. falciparum infections with anaemia [P. vivax asymptomatic infections were not associated with an increased risk of maternal anaemia in low-transmission settings [Interestingly, while all methods displayed similar accuracy in symptomatic pregnant women, LAMP showed the highest sensitivity (100%) to detect infections in afebrile participants, two times better than LM and RDT (50%). The clinical relevance of pregnant women as asymptomatic parasite reservoirs is not yet fully understood, but in South American countries only the overall prevalence of asymptomatic MiP accounts for 22% of all malaria cases . In high anaemia , 48. Altsettings . In thisP. vivax low-density positive specimen probably due to low parasite density.Regarding placental malaria, LAMP showed a four-fold improvement in sensitivity compared with LM and RDT (22.2%). Similar results have been reported in the literature, showing that LAMP was more sensitive than LM , 30, in Additionally, LAMP could be a useful tool for detecting placental infections in peripheral blood. One of the findings of this study was that approximately half of the placental infections were detected in peripheral blood by LAMP and nPCR, while missed by LM or RDT. This result suggested that most placental infections remain hidden when conventional diagnostic test are used , 49, 50,Last but not least, one of the objectives of the study was to evaluate the feasibility of performing LAMP outside a reference laboratory. As reported in previous studies carried out in field condition –27, LAMPPlasmodium parasites in pregnant women, when compared to LM and RDT. In addition, it is worth noting that some women (4.7%) reported having received anti-malarial treatment during pregnancy. Lastly, the current format of the LAMP kit does not allow differentiating between P. falciparum mixed-species infections and P. falciparum mono-species infections. Nevertheless, by combining the Pan-LAMP and Pf-LAMP kits, it was possible to identify all Plasmodium infections confirmed by nPCR . In line with this, a product able to identify all Plasmodium spp., particularly P. vivax, is needed to guide appropriate malaria treatment in clinical settings.The main limitation of this study was the low number of malaria-positive samples, particularly for placental blood. The current research was linked to a larger cross-sectional project in which sample size was estimated to meet the main objective of the parental study, but not the current sub-study related to LAMP performance in pregnant women. Despite not being powered, LAMP showed an improved performance detecting LAMP showed an improved sensitivity for the diagnosis of gestational and placental malaria, when compared with LM and RDT and high agreement with nPCR, especially for detecting low-density infections and screening malaria in afebrile cases. LAMP represents a highly sensitive and less complex alternative to PCR-based tests for the detection of MiP outside reference laboratories. Although the clinical relevance of low-parasitaemia afebrile cases needs to be further investigated, the current findings highlight the need to revise the current MiP surveillance system, currently relying on LM and RDTs only. This is particularly true in low-transmission settings, such as the Colombian malaria endemic regions, where intermittent preventive treatment is not recommended. In this context, LAMP could be a valuable tool for active case detection of malaria cases during ANC visits and at delivery, helping to prevent malaria-related pregnancy and birth complications.


A marked decline in malaria morbidity and mortality has been reported after the introduction of artemisinin-based combination therapy (ACT) in high malaria prevalence countries in Africa. Data on the impact of ACT and on the prevalence of malaria has so far been scarce for Southwest Tanzania.Plasmodium infection prior to and after the introduction of ACT was compared by logistic regression, with consideration of climatic variability, age, sex, socio-economic status and bed net use as potential confounders.Between 2005 and 2011, a large general population cohort in the Mbeya Region in the south-west of Tanzania has been surveyed within the EMINI-study . Participants were examined once per year, including rapid diagnostic testing for malaria. ACT was introduced in the region according to national guidelines in the time period 2006/2007, replacing sulfadoxine/pyrimethamine as first-line therapy. In four study sites, 6773 individuals who participated in the first two of three consecutive survey visits in the period from 2006 to 2009 were included in this analysis. The prevalence of Plasmodium falciparum infection from 2.5 to 0.3% was shown across the four study sites. The decline was not explained by other factors included in the analysis, therefore, the decline over time most likely reflects the impact of introduction of ACT in the study area.A significant reduction over time in the prevalence of P. falciparum infection after introduction of ACT, which could not be explained by potential confounders. The data suggests that artemisinin-based combinations are not only an effective instrument for reduction of immediate morbidity and mortality, but also for reduction of transmission rates.The longitudinal study showed a significant and relevant decline in the prevalence of  Plasmodium falciparum. This high mortality in Africa is aggravated by the high proportion of deaths in the under-5 age-group, which account for about 90% of all malaria related deaths, more than in any other global region.According to the World Malaria Report 2016, to date still more than 210 million persons suffer from malaria infections every year, with 429,000 malaria deaths in 2015 worldwide. The major burden of malaria still lies within Africa with more than 190 million cases and 394,000 deaths annually. Almost all malaria cases in sub-Saharan Africa are caused by the species The East-African country Tanzania has a total population of 45 million, of whom 44% are under the age of 15, and 15% under the age of 5 years. A Tanzanian has a combined life expectancy at birth of 56 years, the total fertility rate is 6.3 children per woman, the annual population growth rate is 2.7% [In order to tackle this problem, particularly in countries with a high malaria burden, which are at the same time low-resource-countries, global stakeholders, such as the WHO, the Global Fund to Fight AIDS, Tuberculosis and Malaria and the Gates Foundation have engaged in promoting aims of malaria reduction that have been set forth in the Millennium Development Goals. Consecutively the World Health Assembly and the Roll Back Malaria initiative have envisaged a reduction by 75% in malaria disease burden between the years 2000 and 2015. Interventions include vector and exposure control through indoor residual spraying (IRS), distribution of insecticide-treated bed nets (ITN), introduction of RDT for differentiation between true malaria cases and non-malarial febrile illnesses, and introduction of artemisinin-based combination therapy (ACT) as first-line treatment –8. HowevEven after the large-scale implementation of rapid diagnostic testing and ACT in Tanzania, high prevalences of parasitaemia in many regions imply a persistent risk of transmission to vulnerable populations, such as infants. In a study from Northern Tanzania in 2012/2013, thus well after the introduction of ACT and RDTs, a prevalence of plasmodium infection of 12.8 and 11.0% were detected in pregnant women and in infants respectively, regardless of presence of symptoms . AnotherIn this study, the prevalence of malaria RDT positivity before and after the introduction of ACT was compared in order to estimate the effect of ACT introduction on malaria in the study population.The Mbeya Region with a population of 2.7 million is located in the Southwest of Tanzania, a highland area with mountains ranging up to 3000 m in altitude . The lowThis study is an observational, longitudinal and closed cohort study, based on the EMINI  cohort, established since May 2006 by the Tanzanian National Institute of Medical Research-Mbeya Medical Research Centre (NIMR-MMRC) in collaboration with the Division of Infectious Diseases and Tropical Medicine, University Hospital, LMU Munich. The design follows a pre- and post-intervention structure, where the intervention was a switch of government first-line malaria treatment from SP to ACT in the whole population. In order to properly represent the regional diversity in terms of geography, urbanization and living conditions, nine study sites in the Mbeya Region were purposively selected for participation in the EMINI cohort, covering characteristics, such as urbanization and different levels of altitude. In preparation for EMINI, a complete population census was performed in all nine sites. In order to get a geographically balanced sample and avoid random spatial clustering, each site was then subdivided into 6–10 areas, from each of which 10% of households were randomly selected for participation in the EMINI cohort. All household members of all ages from these selected households were then invited for participation, resulting in a cohort of more than 18,000 individuals in the nine EMINI sites. Because the introduction of ACT coincided with the set-up of the cohort in five of the nine sites, no consistent pre-ACT baseline data is available for these sites. Hence, only the remaining four sites, where ACT was introduced after completion of the first baseline visit were included in this analysis, comprising 7957 individuals. Out of these, 1184 individuals were not present at the second household visit, resulting in 6773 individuals who were included in our analyses.The included four sites are the rural areas of Igurusi , Mlowo , Santylia  and Isongole  , July 2007 and July 2008 (visit 2), and July 2008 and June 2009 (visit 3). During each round, the same sites and households were visited at about the same time of the year.Plasmodium falciparum infection was tested using the ICT Malaria Combo Cassette Test . This RDT is an immunochromatography test with antibodies against histidine-rich protein 2 (HRP2), which is species-specific for P. falciparum, in combination with antibodies against aldolase which is detected in P. falciparum, Plasmodium malariae, Plasmodium ovale and Plasmodium vivax infections. For this study P. falciparum positivity was defined as any RDT result with both a positive control line and a positive HRP2 line, regardless of the result of the aldolase line. The test was performed on every participant at each household visit, regardless of clinical signs of malaria. Participants with a positive result were offered immediate treatment with ACT. Since ACT was introduced in the entire region, no control group continuing to be exposed to the previous first-line treatment could be included in the analysis. RDTs and immediate treatment provision, restricted to confirmed cases only, were already in place in all sites prior to the study initiation.Information on personal and household characteristics  was collected using questionnaire based face-to-face interviews, which were held in Kiswahili. Bed net ownership and housing quality was ascertained by visual inspection. A socio-economic status (SES) score was constructed as a composite and standardized variable based on a principal component analysis of several household assets and housing quality , 16.The geographical position of each participating household was determined using handheld GPS  receivers. Vegetation characteristics were quantified using annual averages of the Normalized Difference Vegetation Index (NDVI), which is based on satellite measurements as provided by the US National Aeronautics and Space Administration (NASA). Differences in light absorption spectra measured by spectral cameras in satellites allow the assessment of vegetation density, which in turn allows conclusions on previous floral growth conditions, such as humidity and rainfall profile. This vegetation data is available from the NASA Moderate-Resolution Imaging Spectroradiometer (MODIS) Terra Mission , 18. NASP. falciparum infections, prevalences for visit 3 are also reported.The performed analyses are based on data before (visit 1) and after (visit 2) introduction of ACT. In order to corroborate the sustainability of reduction in All interview and medical examination data were collected using hand-held personal digital assistance devices and then imported into a Microsoft Access  database. Laboratory results were documented on paper forms, double entered into a Microsoft Access database and compared and corrected for data entry errors. Data analysis was performed using Stata version 14.2 . The univariable description of the cohort uses proportions to summarize categorical variables. Continuous variables are summarized by their median and interquartile range, since none of them was normally distributed according to the Shapiro–Francia test.Two mixed effects multivariable logistic regression models with random effects for study site and household to adjust for clustering were constructed. The first model examines the effects of various factors on the baseline prevalence of malaria RDT positivity, with the RDT result of visit 1 as the outcome and sex, age, bed net ownership, SES and NDVI as covariates. The second model targets the change in RDT positivity from visit 1 to visit 2. Change is dichotomously defined as a change from positive in visit 1 to negative in visit 2 versus all other scenarios combined . In this model the independent variables sex, age, change in bed net ownership, change in SES and change in NDVI from visit 1 to visit 2 were included. In 4 out of 6773 participants data on SES was missing, therefore the models were run on 6769 participants.This study follows the principles of the Helsinki Declaration. All participants had signed an informed consent form prior to inclusion. For all minors below the age of 18 years their legal guardians signed the informed consent form and children between 12 and 18 years additionally signed an assent form. Ethics approval of the cohort study within the EMINI framework was obtained from the Tanzanian National Institute for Medical Research.The lower lying sites of Igurusi and Mlowo are characterized by lower NDVI values than Santylia and Isongole. The numbers of inhabitants of the four included sites according to the EMINI census data, the mean altitude and the mean vegetation-index of households at the respective sites are detailed in Table Table The four sites showed very different NDVI distributions, which corresponds to the varying physiognomy of the locations. Most NDVI values were in the range between 0.3 and 0.6, and thus between grassland and temperate/tropical forest according to NASA . This reP. falciparum infection were found  than all other age groups  than females of the same age group .Across all four included sites, 160 out of 6773 individuals were RDT positive at visit 1 and RDT negative at visit 2; six individuals were RDT positive at both visit 1 and 2; and 21 individuals were RDT negative at visit 1 and turned positive at visit 2; all remaining individuals were RDT negative at both visit 1 and visit 2. At baseline, participants between 10 and 20 years of age were more often The proportion of bed net owners corresponded to the prevalence of malaria in the sites, with more bed net owners in the lower lying sites where malaria infection is common. As for the malaria high-prevalence site Igurusi, where also the proportion of bed net owners was high, individuals from households with bed nets showed lower prevalences of parasitaemia compared to individuals from households without bed nets located in the same site Table . Figure P. falciparum RDT positivity dropped substantially in all four groups, including participants who owned a bed net at the first visit but had lost it before the second visit.Change in bed net ownership between visits 1 and 2 and its potential influence on change in malaria prevalence was further analysed for Igurusi, the site with the highest malaria prevalence. Table P. falciparum RDT results for the first and second visit were included in the two uni- and multivariable mixed effects logistic regression models. The first model aims to identify factors that might influence P. falciparum infection at the first visit. The second model examines the influence that potential change of the above identified factors between the visits might have on the decline in malaria between visits. The first model revealed significantly higher odds of P. falciparum infection for participants between 5 and 10  and between 10 and 20 years of age  compared to children below 5 years. Bed net ownership, and SES were negatively associated with RDT positivity whereas NDVI showed a positive association. These associations were relatively strong, but significant only in univariable, and not in multivariable analysis . However, when adjusting for site and household in the mixed effects models, the odds of losing infection were considerably lower for participants who lost their bed net compared to those with unchanged bed net ownership in both the uni-  and multivariable analysis , whereas the odds for those who obtained a bed net were nearly the same as for those where bed net ownership did not change.Although unchanged between visits, age at visit 1 and gender were included into the models for loss of rs Table . The mulP. falciparum infection between visits was higher when NDVI increased, which is counterintuitive.Change in SES showed a very weak and non-significant negative association with loss of malaria infection. Change in NDVI showed a stronger but non-significant positive association, in both the uni- and multivariable analysis , meaning that loss of P. falciparum prevalence. In this study, malaria status was determined by RDT, which reflects common procedures in health care systems in malaria endemic countries. This strategy is somewhat hampered by limited sensitivity and specificity, which may be particularly challenging the positive predictive value of any given RDT in a setting where malaria prevalence has been already substantially reduced. Between baseline (visit 1) and the first follow up (visit 2) an overall 83.7% reduction in P. falciparum prevalence could be shown. The effect was sustained and even consolidated afterwards, resulting in an overall prevalence of P. falciparum RDT positivity of only 0.3% at visit 3 compared to 2.5% at baseline. Similarly promising findings have been reported from other countries that are endemic for malaria [In the EMINI cohort, replacement of sulfadoxine/pyrimethamine (SP) by ACT as first-line therapy in the years 2006 and 2007 resulted in a significant and relevant reduction of  malaria .P. falciparum infection, an age dependent distribution of prevalence, which has been described in other studies [P. falciparum infected than females, as has been shown in other studies [P. falciparum infection, although these associations were significant only in univariable analysis  were implemented in the region during the study period. Although other uncontrolled factors also might have played a role in this, the change in first-line treatment as corroborated through this study seems to sufficiently explain the observed change in P. falciparum prevalence.The most important limitation of this study is the lack of a control group which would have enabled us to directly compare the impact of ACT treatment on malaria with that of SP treatment, the previous standard of care. Instead the analysis relies on a before/after comparison, which might have been confounded by other factors that changed between the two visits. In order to overcome this, the most important factors that were associated with malaria at baseline were identified, and an analysis was performed in order to examine whether their change could explain the observed drop in A selection bias imposed by the exclusion of participants that had missed consecutive visits cannot be ruled out.The validity of NDVI as a proxy indicator of humidity and, therefore, of favourable conditions for vector habitats is limited. NDVI has shown to correlate with rainfall only in defined lower ranges of annual rainfall. Mbeya region with about 800 mm annual rainfall is already exceeding the upper limit of linear correlation. In addition, many other factors such as lag time and fine scale variability over time were not considered , 24. AnoP. falciparum infection implies a lower transmission and, therefore, lower morbidity and mortality in vulnerable age groups, which comprise children and adolescents between 5 and 20 years of age. The study area is by now considered a low risk area for malaria transmission. At the same time the local health authorities have adopted an improved approach of antimicrobial stewardship with the introduction of RDTs and by reserving anti-malarial treatment for patients with a positive RDT result. In addition, this development improves the adequate use of antibiotics, which are not administered as a fixed combination with anti-malarials anymore. These are important prerequisites for avoiding development of resistances against first line anti-malarials currently in use.The introduction of ACT in the Mbeya Region coincides with a relevant reduction in malaria prevalence within a very short period of time. Since this decrease is not explained by other factors included in the presented analyses, the investigators believe that it reflects the effect of switching to ACT as first-line malaria therapy. Lower prevalence of


Despite the biological plausibility of hotspots fueling malaria transmission, the evidence to support this concept has been mixed. If transmission spreads from high burden to low burden households in a consistent manner, then this could have important implications for control and elimination program development.Plasmodium falciparum infections were determined by polymerase chain reaction and analyzed using a geostatistical model.Data from a longitudinal cohort in The Gambia was analyzed. All consenting individuals residing in 12 villages across the country were sampled monthly from June (dry season) to December 2013 (wet season), in April 2014 (mid dry season), and monthly from June to December 2014. A study nurse stationed within each village recorded passively detected malaria episodes between visits. Household-level observed monthly incidence ranged from 0 to 0.50 infection per person (interquartile range = 0.02–0.10) across the sampling months, and high burden households exist across all study villages. There was limited evidence of a spatio-temporal pattern at the monthly timescale irrespective of transmission intensity. Within-household transmission was the most plausible hypothesis examined to explain the observed heterogeneity in infections.Within-village malaria transmission patterns are concentrated in a small proportion of high burden households, but patterns are stochastic regardless of endemicity. Our findings support the notion of transmission occurring at the household and village scales but not the use of a targeted approach to interrupt spreading of infections from high to low burden areas within villages in this setting.The online version of this article (10.1186/s12916-018-1141-4) contains supplementary material, which is available to authorized users. Within populations, heterogeneity in exposure to malaria has been widely documented; it is generally estimated that 20% of the population experience 80% of the disease burden –3. The sThe consistent presence of spatial clusters of high malaria burden within populations contributed to the hypothesis that there may be hotspots, or certain households, or subsets of households within foci  that fuel transmission . The numThe notion of hotspots as intrinsic drivers of malaria transmission being an inherent part of the transmission landscape is plausible with risk being driven by macroscale and microscale characteristics , 12. ForAlthough biologically plausible, the evidence to support the concept of hotspots, here considered as a single household or group of high burden households within foci, fueling transmission has been mixed. For example, a recent trial targeting serologically defined hotspots of exposure failed to observe any sustained reduction in transmission outside of the targeted area . TransmiIn this study, we conducted a spatio-temporal analysis on a full population cohort distributed in six pairs of villages across The Gambia. The aim of this research was to establish if predicted risk of malaria transmission intensity exhibits a consistent pattern, meaning the risk of malaria moving from a high burden household or a group of households to neighboring households, over time. If the expected pattern exists, we aimed to identify at what transmission intensity this dynamic becomes apparent. In case of limited evidence to support the hotspot pattern, some potential drivers of any observed heterogeneity were explored.Malaria transmission in The Gambia is highly seasonal and occurs during and soon after the rainy season, typically between August and December. Epidemiological data from the study cohort has been recently described . BrieflyPlasmodium falciparum infections using polymerase chain reaction (PCR). All febrile individuals (auxiliary temperature ≥ 37.5 °C or history of fever in the last 24 h) were screened for malaria by rapid diagnostic test (RDT), and if positive they were treated with artemether-lumefantrine according to national guidelines. A study nurse was stationed within each village and recorded all malaria episodes between monthly visits, including administering an RDT and collecting a blood sample on filter paper.Finger prick blood samples were collected on filter paper for identification of Anopheles mosquito and can be directly measured using the entomological inoculation rate (EIR) [P. falciparum parasite rate (PfPR) is a known correlate to EIR; it provides a measure of transmission intensity and is a more operationally feasible metric to generate [Malaria parasites are transmitted to humans via the bite of an infected te (EIR) , 27. Thegenerate . Using Pgenerate . A BayesModels were adjusted for sample date, distance to road, distance to river, and mean monthly rainfall. The distance to river and road variables were determined by extracting the relevant features from pan-sharpened Landsat 8 imagery and using the gDistance function in the rgeos package  to estimThe observed overdispersed distribution of infection counts has been used to support the notion of malaria hotspots . HoweverIn total, 41,548 monthly observations were available from 360 households across 14 sampling time points. The size of households ranged from a single person to 78 individuals, and the residents had a similar age distribution between villages  for all study villages (panels) according to the spatio-temporal model. The size and color of the circles are scaled according to prevalence. Each household is identified by a black dot. Households with a predicted PCR prevalence between 0 and 1% are identified in greyscale. (MP4 285 kb)Monthly predicted PCR prevalence per household Additional file 3:Results of analysis stratified by whether an infection was symptomatic or asymptomatic. Symptomatic infections were those individuals with fever and a confirmed infection by rapid diagnostic test (RDT), whereas asymptomatic infections were those who were febrile but RDT negative and positive by polymerase chain reaction (PCR) or were afebrile and positive for malaria by PCR. The distribution of prevalence of infection type per month per village as well as the predicted monthly prevalence of each infection type per village are shown. (DOCX 4478 kb)Additional file 4:panel represents a household, and each row within the panel represents an individual residing in that household. Individuals are ordered by increasing age with the youngest on top within each panel. Each column within each grid represents a sampling month starting in June 2013 through December 2014. (DOCX 4496 kb)Heat maps for all villages, removing households with no infections and individuals with 5 or fewer time points sampled. Each


Plasmodium falciparum and bacterial coinfection” “Plasmodium falciparum RDT test results in children in endemic areas” in Google Scholar and PubMed.Rapid diagnostic tests have been of tremendous help in malaria control in endemic areas, helping in diagnosis and treatment of malaria cases. It is heavily relied upon in many endemic areas where microscopy cannot be obtained. However, caution should be taken in the interpretation of its result in clinical setting due to its limitations and inherent weakness. This paper seeks to present the varying malaria RDT test results, the possible interpretations and explanation of these results common in endemic regions. Published works on malaria RDT studies were identified using the following search terms “malaria RDT in endemic areas”, “Plasmodium or a co-infection of bacteria and P. falciparum. False RDT negative results can be seen in febrile patient with P. falciparum infection in prozone effect, Histidine rich protein 2 (HRP2) gene deletion and faulty RDT kits. Hence, a scale up of laboratory facilities especially expert microscopy and other diagnostic tools is imperative.The review results show that RDT positive results in febrile patients can either be true or false positive. True positive, representing either a possible single infection of  Prompt and accurate malaria diagnosis is important to malaria control programs in endemic regions as it limits over diagnosis as well as provide evidence of infection that requires prompt and adequate treatment . In 2010Plasmodium falciparum histidine rich proteins-2 (HRP2) from SD Bioline Malaria Ag Pf®  and First Response Malaria Ag Pf ®  . Th. ThP. faic areas  and theyP. falciparum infection together with a bacteria, making it a malaria and bacteria co-infection, which is another common presentation in malaria endemic area (Fig. Toxoplasma gondii infections (Fig. There is also another possibility where the fever is indeed caused by rea Fig.  16–18].–18.P. faons Fig.  19, 20], 20P. faAntimalarial treatment is not recommended in RDT negative patient with fever, as per the current malaria treatment protocol, such fevers are considered not to be caused by malaria. However, cases of false negative have been reported in patient with high parasite densities, a phenomenon called the prozone effect Fig.  12]. Th. Th12]. P. falciparum HRP2 have also been implicated in some cases of false negative RDT (Fig. Genetic variation of False negative can also occur at low parasite densities defined as < 100 asexual parasites/micro liter of blood or < 0.002% of red blood cells infected (Fig. RDT negative result in a patient with fever, have given rise to another nagging problem of over prescription of antibiotics , 29. TheP. falciparum with RDT probably has an asymptomatic infection (Fig. An afebrile patient testing positive for ion Fig. . The prePositive RDT results without fever can also occur in patients recovering from malaria after treatment Fig.  38]. Th. Th38]. In some situations, there might not be any parasite or antigens at all in the person’s blood stream and RDT will still be positive. Certain non-fever causing diseases can produce heterophile antigens that can react with test kits antibodies to produce a false positive results . False pA patient without fever and testing negative for malaria with RDT is most likely free from malaria. However, if they are asymptomatic, their true status will evade RDT especially if the parasite density is very low Fig.  12]. It. It12]. The introduction of RDTs have reduced over prescription and indiscriminate use of antimalarial in endemic areas. However, RDT may be flawed by some weakness in estimating parasite densities and inability to detect parasites at low densities. Furthermore, its inability to differentiate between the exact causes of fever in patients with malaria and bacterial infection or other fever causing pathogens has made it dicey in managing febrile patients with antimalarial alone. There is also the problem of false positive results from diseases that produce heterophile antigens and false negative from, prozone effect, HRP2 gene deletion and poor quality RDT.These weaknesses in malaria RDT kits shows that it cannot solve all the problems of malaria diagnosis in endemic areas. The success of RDT cannot drown the nagging need of a scale up of laboratory facilities in resource limited settings. Expert microscopy should be the goal, together with other necessary laboratory tools to aid in the overall diagnosis of febrile and afebrile patients in malaria endemic areas.Two search engines were used for this review and the researchers acknowledge that it limited the number of studies identified with the subject of interest. This notwithstanding, the articles retrieved present a valid reasoning on the need to be circumspect in the interpretation of RDT test results in endemic regions.


Plasmodium falciparum extensively remodels the infected erythrocyte cellular architecture, conferring cytoadhesive properties to the infected erythrocytes. Cytoadherence plays a central role in the parasite's immune-escape mechanism, at the same time contributing to the pathogenesis of severe falciparum malaria. In this review, we discuss the cytoadhesive interactions between P. falciparum infected erythrocytes and various host cell types, and how these events are linked to malaria pathogenesis. We also highlight the limitations faced by studies attempting to correlate diversity in parasite ligands and host receptors with the development of severe malaria.After a successful invasion, malaria parasite  Plasmodium falciparum is the primary cause of severe disease and death   . During er cells . Inside P. falciparum infection is the cytoadherence phenomenon associated with the late stage-IRBC   via interactions with the A antigens on the URBCs  encoded by multigene families, namely; (PfEMP1) , 13, Sub(PfEMP1) , and rep(PfEMP1) . The tem(PfEMP1) , 17, fol(PfEMP1) , then ST(PfEMP1) –21. In a(PfEMP1) . The rolhe URBCs , some RIhe URBCs . This dihe URBCs , 21. By he URBCs  and immuhe URBCs . Hence, he URBCs –56. In ghe URBCs , 58. Imphe URBCs .P. falciparum IRBCs can adhere to each other through platelet bridges, forming aggregates of IRBCs, a mechanism defined as autoagglutination  and leukocytes  , 60–62. tination –65. Thistination . These dP. falciparum merozoite invading the RBCs, the relatively low intra-erythrocytic viscosity of liquid hemoglobin is transformed into viscous gel-like cytoplasm of a developing IRBC  onto its surface  collected from the peripheral circulation are essentially similar to the sequestering late stage-IRBCs, the findings from in vitro rosetting studies (conducted on these parasites after ex vivo maturation) may not imply the actual situation in vivo since the recruited IRBCs are not given an equal exposure to URBCs and endothelial cells in rosetting assays, which raises doubts if rosetting ever happens in vivo. If this were the case, the rosetting phenomenon seen in vitro is merely an indication of “IRBC's stickiness,” where the IRBCs would probably adhere to the microvasculature wall in vivo. Such situation makes it difficult to extrapolate the importance of rosetting in contributing to pathogenesis of severe malaria.Importantly, all rosetting studies have been conducted under P. falciparum-IRBCs in peripheral blood of a patient suffering hyperparasitemia has been reported  and over-saturated relative to the total surface area of deep vasculature endothelial cells available for IRBC cytoadhesion. Thus, the IRBCs that do not get to cytoadhere to endothelia will be available in peripheral circulation. Of note, the availability of late stage reported . When threported , 174–176reported , 177 havreported . This hyreported , 179. Neex vivo system using rat isolated mesocecum that rosetting IRBCs contributed to microvasculature occlusion under flow condition. In this system, rosette-forming P. falciparum IRBC formed aggregates at venule junction, which restricted the flow. These aggregates were eventually dissociated slowly by the induced upstream force mimicking blood flow, leaving some IRBCs still attached to the endothelial cells afterwards. Here, rosetting was seen as an event that “widens the zone of vasculature occlusion.” With merely IRBC-endothelial cytoadhesion, blockade may only happen at fine capillaries with lumen size (~5–10 μm) close to the size of a normal RBC. However, sites of IRBC sequestration encompass capillaries and venules (lumen size of ~ 7 μm to 1 mm)  has its blood flow hampered significantly in advance by the IRBC-endothelial cytoadhesion. Alternately, the rosetting IRBCs may be adhered securely to the endothelial cells via platelet as elaborated earlier . Regardlto 1 mm) , 181. Asto 1 mm) , even wirosettes , 183. Bencreases . Howeverom India –190, sugum IRBCs . TherefoSl2 allele was reported to confer protection against cerebral malaria, possibly due partly to its reduced rosetting phenomenon in addition to other factors, as suggested by the authors; whereas McCb allele served as a risk factor to develop cerebral malaria, but arises from selection probably due to survival advantage against other infections  was reported to be a risk factor for severe malaria in Thai population . Anotherfections . Based oP. falciparum that do not kill its human host while trying to survive within its host would be selected over time. As elaborated earlier, the P. falciparum late stage-IRBCs require sequestration to escape host's immune system. However, the endothelial cytoadhesion-mediated sequestration causes potentially fatal outcomes to the host, which is disadvantageous to the parasite as well.Parasitism is a relationship between two organisms where one party (the parasite) causes harms to the other party (the host) while living in/on the host. Evolution, through selection process, tends to drive this relationship toward a relatively “peaceful” one, where the selected parasites cause as little harm as possible to the host while the host is evolved and adapted to accommodate the parasite, without eliciting much immune response against the parasites. Following this evolutionary point of view, it would make more sense that P. falciparum serve as the parasite reservoirs during dry seasons, when the Anopheline mosquito number is low  following microvasculature occlusion by the IRBCs are rarely seen  with similar binding strength (The manifestation of rosetting relies on the stability of rosetting complex under flow conditions. Rosettes are stable under sheared conditions, from very low shear forces to shear stress of about 1.5 Pa , 207, whte assay , where aely seen . Intereschannels . Althougstrength , 183, anstrength , 94.Another interesting evidence that suggests rosetting as “counter-endothelial cytoadhesion” stems from studies that investigated effects of sulfated glycoconjugates on rosetting and IRBC-endothelial adhesion. A number of sulfated glycoconjugates such as fucoidan, dextran sulfate, and heparin can disrupt rosettes , 211. HoP. falciparum (To date, most of the studies on human host-malaria parasite interactions in the context of IRBC cytoadherence focus on injuries sustained by the host from the parasites. Whether there is any “damage control” approach by either party in this parasitism relationship remains unknown. This is rather bizarre for a parasitism relationship with such a long evolutionary history. Importantly, as mentioned earlier, the parasites can persist in some human hosts for a very long time without causing signs and symptoms. This suggests that the survival-essential phenomena of the parasites, such as deep vasculature sequestration to avoid splenic clearance, can be tolerated by the host, and these phenomena may be the result of host-parasite interactions. Interestingly, the host-derived complement factor D, albumin, and anti-band 3 IgG have been reported as the rosette-promoting factors for lciparum . On top lciparum . Such selciparum . Neverthlciparum , 215. InAs stated earlier, the adherence of IRBCs to endothelial cells trigger endothelial activation and inflammation. Subsequently, the level of various cytokines at the inflamed site is increased. Weibel-Palade body is one of the components being released by endothelial cells upon the onset of endothelial activation. As elaborated earlier, of the various components found within Weibel-Palade bodies, some have been associated with severe malaria pathogenesis and some have important role in regulating homeostasis in vasculature. It would be interesting to examine the effects of all key components in Weibel-Palade bodies on the dynamics of IRBC cytoadherence, as well as other interplays between the host and the parasite.Based on the currently available literature, it is likely that the malaria-related cytoadherence phenomena may give rise to complex host-parasite immunopathological interactions, starting from IRBC-endothelial cytoadhesion at the microvasculature . This reUndeniably, IRBC cytoadhesion is an important aspect in the pathogenesis of malaria, and a key interplay between the malaria parasite and its host. However, there are many “unresolved issues,” such as the role of rosetting and feedback responses by the host following malaria-induced vascular injury, which deserve further research attention. A better understanding on these issues will enable us to understand malaria pathogenesis better, and design a reliable and safe clinical intervention strategies to improve the clinical management of malaria patients.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.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.


Plasmodium falciparum infection, but its role in Plasmodium vivax infection is unknown. CRP loss increases RBC susceptibility to macrophage clearance, a process that is also regulated by CD47. We compared CRPs and CD47 expression on infected and uninfected RBCs in adult patients with vivax and falciparum malaria and different anemia severities from Papua, Indonesia. Complement activation and parasite-specific complement-fixing antibodies were measured by ELISA. Levels of CR1 and CD55 were reduced in severe anemia in both falciparum and vivax malaria. Loss of CRPs and CD47 was restricted to uninfected RBCs, with infected RBCs having higher expression. There was no association among complement-fixing antibodies, complement activation, and CRP loss. Our findings demonstrate that CRP loss is a pan-species, age-independent mechanism of malarial anemia. Higher levels of CRP and CD47 expression on infected RBCs suggest that parasites are protected from complement-mediated destruction and macrophage clearance. Lack of associations between protective antibodies and CRP loss highlight that complement pathogenic and protective pathways are distinct mechanisms during infection.Anemia is a major complication of malaria, driven largely by loss of uninfected RBCs during infection. RBC clearance through loss of complement regulatory proteins (CRPs) is a significant contributor to anemia in  Loss of complement regulatory proteins (CRPs) on uninfected RBCs is a pan-species and age-independent driver of malaria anemia. Plasmodium falciparum and Plasmodium vivax infection. Anemia is a common clinical manifestation of malaria and a major cause of morbidity and mortality among young children and pregnant women . Expression of RBC CR1 and CD55 differed significantly among patients with different degrees of anemia . No differences in CD47 expression were observed across anemia categories , along with levels of complement activation , within our patient cohort. There was no association between levels of C1q-fixing antibodies and CRP RBC expression for either P. falciparum– or P. vivax–infected malaria patients  or P. vivax–infected  patients  is expressed on reticulocytes and has been identified as a key invasion ligand for P. vivax , mild anemia (MA), and severe anemia (SA), based on World Health Organization anemia categories . Mild/moP. falciparum D10-GFP and 3D7 strain were cultured and synchronized as described previously  parasites were purified from uninfected RBCs using the VarioMACS magnet system and CS column (Miltenyi Biotec) . Purifien = 8) and incubated for 24 hours. Another set of matched RBCs without schizonts were used as controls. After 24 hours, the culture samples were stained and analyzed by flow cytometry.To measure expression of CRPs in parasite culture following invasion, purified schizont-stage D10-GFP parasites were added to RBCs from healthy and malaria-naive individuals (n = 6). Antibody staining of CRPs was done individually with the addition of SYBR Green (Thermo Fisher Scientific) for parasite staining, and staining condition was optimized to maximize fluorescent intensity (P. vivax sample staining to the exclude CD71+ (immature reticulocytes) population  that would normally yield 2 × 108 merozoites  was added and C1q was detected with 1:2,000 rabbit anti-C1q antibodies (Dako) and 1:4,000 goat anti-rabbit HRP (Bio-Rad). Tetramethylbenzidine (MilliporeSigma) was added as a substrate, and the reaction was stopped with 1 M HCl. Absorbance of the reaction was read at 450 nm.ELISA procedure was carried out as described previously , 52. Ninrozoites . WashingP. vivax patient samples, the plates were coated with recombinant PvMSP3α block I–II region  protein. The recombinants proteins were amplified from P. vivax (Belem strain), expressed with vector containing a C-terminal 6× His Tag, and purified as described previously  and P. vivax–infected  patients were available for complement activity assay. Concentration of complement activation products (C3a and C5a) was measured using commercial ELISA kits (eBioscience) as per the manufacturer’s instructions.Plasma samples from P value less than 0.05 was considered significant.All analyses were performed in STATA (version 15.0), RStudio (version 1.0.153), and GraphPad Prism (version 7.03). Differences in CRPs and CD47 expression on uninfected RBCs were compared among anemia groups using Kruskal-Wallis and Mann-Whitney nonparametric test. Correlations between the complement-fixing antibodies and CRPs and between complement activation and Hb level were determined using Spearman’s nonparametric method. For the comparison of CRPs and CD47 between uninfected and infected RBCs, Wilcoxon signed-rank test was used. A Written informed consent was obtained from all study participants or, in the case of children, parents or guardians. For clinical cohorts, the study was approved by the ethics committees of the Northern Territory Department of Health , Menzies School of Health Research, the Indonesian National Institute of Health Research and Development , and the Oxford Tropical Research Committee .DAO and MJB designed research study. DAO conducted experiments. DAO, MJB, JGB, NMA, and RNP analyzed data. EK, JRP, NMA, and RNP supervised the clinical studies and sampling. DAO, MJB, and NMA led manuscript preparation with feedback from all authors.


Although poor complementary feeding is associated with poor child growth, nutrition interventions only have modest impact on child growth, due to high burden of infections. We aimed to assess the association of malaria with linear growth, hemoglobin, iron status, and development in children aged 6–18 months in a setting of high malaria and undernutrition prevalence.Prospective cohort study, conducted in Mangochi district, Malawi. We enrolled six-months-old infants and collected weekly data for ‘presumed’ malaria, diarrhea, and acute respiratory infections (ARI) until age 18 months. Change in length-for-age z-scores (LAZ), stunting, hemoglobin, iron status, and development were assessed at age 18 months. We used ordinary least squares regression for continuous outcomes and modified Poisson regression for categorical outcomes.p = 0.023), anemia  and better socio-emotional scores , but not with change in LAZ, haemoglobin, iron status or other developmental outcomes. Diarrhea incidence was associated with change in LAZ , stunting , and slower motor development. ARI incidence was not associated with any outcome except for poorer socio-emotional scores.Of the 2723 children enrolled, 2016 (74.0%) had complete measurements. The mean (standard deviation) incidences of ‘presumed’ malaria, diarrhea, and ARI, respectively were: 1.4 (2.0), 4.6 (10.1), and 8.3 (5.0) episodes/child year. Prevalence of stunting increased from 27.4 to 41.5% from 6 to 18 months. ‘Presumed’ malaria incidence was associated with higher risk of stunting  and NCT01239693 . Although poor complementary feeding is associated with poor child growth, many interventions designed to improve complementary foods only have modest impact on growth , possiblLongitudinal studies have reported a significant inverse association of diarrhea with growth –9. HowevThe International Lipid-based Nutrient Supplements (iLiNS) Project DOSE and DYAD-M studies were randomized controlled trials conducted in Malawi to study the impact of lipid-based nutrient supplements (LNS) on growth of children , 16. TheThe iLiNS-DOSE and iLiNS-DYAD-M studies were conducted in one public district hospital (Mangochi), one mission hospital (St Martins), and two rural public health centers (Lungwena and Namwera) in Mangochi District, Southern Malawi. The total catchment population of 180,000 largely subsisted on farming and fishing. In Malawian children aged < 5 years, the prevalence of reported fever , diarrhea and ARI was 29, 22 and 5%, respectively, with seasonal fluctuations . MalariaIn the iLiNS-DOSE study, 6-mo old children were randomly allocated to one of five intervention groups provided with different doses or formulations of LNS or to a control group that did not receive LNS during the 12-mo study period, between November 2009 and May 2012. In the iLiNS-DYAD-M study, pregnant women < 20 weeks’ gestation were randomly allocated to one of three groups to receive iron and folic acid (IFA), multiple micronutrients (MMN) or a small-quantity (20 g) of LNS daily. After delivery, women in the IFA group received placebo tablets, while MMN and LNS supplementation was continued up to 6 mo postpartum. Children of mothers in the LNS group also received LNS 10 g twice daily from age 6 to 18 mo. This study was conducted from February 2011 to April 2015. Details of study design, randomization and enrolment for the two studies were explained in the main outcome papers .In both studies, research assistants visited the children’s homes every week from age 6 to 18 mo to interview the guardians about the child’s health in the previous 7 days using a structured questionnaire. The information was complemented by a picture calendar filled out by the guardians daily to aid memory of their children’s morbidity status. The use of maternal interviews as a means of collecting data on child morbidity has been validated in previous studies , 20. TheAnthropometric measurements were taken at age 6 mo and 18 mo. Study anthropometrists measured the infant’s length with a high-quality length board  and recorded it to the nearest 1 mm. They weighed unclothed infants with electronic infant weighing scale , recording to the nearest 10 g. The anthropometrists were trained and their measurement reliability was verified at the start of the study and at 6-mo intervals thereafter with methods adapted from the procedures used in the WHO Multicentre Growth Reference Study . The antWe assessed iron status at age 6 mo and 18 mo by measuring the zinc protoporphyrin (ZPP) concentration in unwashed venous blood sample using a hematofluorometer . About 5–7 ml of blood was collected by venepuncture using a 23-gauge needle into 7.5 ml evacuated, trace element-free polyethylene tubes containing lithium heparin . The samples were kept covered in aluminium and away from light, in a refrigerator or on ice, and processed within 2 h of collection. We measured blood hemoglobin (Hb) concentration at age 6 mo and 18 mo from a drop of blood taken from a finger prick and collected in a microcuvette. Hb analysis was conducted on-site using a Hemo-Cue instrument .We assessed fine and gross motor development at age 18 mo using the Kilifi Developmental Inventory (KDI) developed in Kenya . LanguagWe used a presumptive diagnosis of malaria derived from episodes of fever during the previous week, reported by the guardians. To ensure the diagnoses were mutually exclusive, we created an algorithm whereby any fever with a diarrhea episode (three or more loose stools in 24 h) was categorized as diarrhea; any fever in the presence of any respiratory symptoms  was categorized as ARI. ‘Presumed’ malaria was defined as any fever episode in the absence of diarrhea and respiratory symptoms.An episode of ‘presumed’ malaria, ARI or diarrhea was defined as the period starting from the day the child had the symptoms when preceded by at least 2 days of no symptoms or no data. The episode ended on the last day the child had the symptoms which was then followed by at least 2 symptom-free days. Incidence of ‘presumed’ malaria, ARI or diarrhea for each child from age 6 to 18 mo was calculated as total episodes / total follow up years at risk.Longitudinal prevalences of common childhood symptoms  from age 6 to 18 mo were defined as the number of days with the symptom divided by the total number of days of observation for each child .We calculated age- and sex-standardized anthropometric indices  based on the WHO Child Growth Standards  and consIron deficiency at age 6 mo and 18 mo was defined as whole blood ZPP > 70 μmol/mole heme . Anemia From the child development data at age 18 mo, fine motor scores were calculated as the sum of 34 KDI fine motor items, each scored 0 or 1, gross motor scores were calculated as the sum of 35 KDI gross motor items, each scored 0 or 1  and vocaWe included in the analysis children who had outcomes measured at age 18 mo. For all continuous outcomes, we used ordinary least squares regression to assess the association between malaria incidence and each outcome; and for all binary outcomes, we used modified Poisson regression (with a robust variance estimator) .We first assessed whether the relationship between the predictor and each outcome differed between the two studies. However, the interaction term was not statistically significant indicating that this relationship was not different between the two studies therefore we pooled data from the two cohorts. We then constructed multivariate models to determine which variables independently predicted the outcomes. We included all theoretically relevant variables, regardless of whether they were statistically significant or not after the bivariate analysis. The following variables collected at age 6 mo were included in the models: child sex, LAZ, WLZ, Hb, iron status, maternal education and household food insecurity access (HFIA) score generated by summing the value of responses to nine questions regarding food insecurity . We alsoWe assessed collinearity among the variables (e.g. LAZ vs WLZ at age 6 mo). If the variables were highly collinear (> 0.5), we dropped the one that was less strongly associated with the outcomes. We accounted for intracluster correlation due to twins using generalised estimating equations .We also performed exploratory analyses by using frequency of malaria episodes (from age 6 to 18 mo) as a categorical variable . In addition, we conducted stratified analyses by stunting at age 6 mo. Although we performed bivariate analyses for each individual variable, we will only report the results from multivariate analysis.We used Stata version 14  for all the analyses.Of the 2723 children enrolled in the two study cohorts, 2016 (74.0%) had length measured both at age 6 mo and 18 mo (1417 children from the iLiNS DOSE study and 599 children from the iLiNS DYAD-M study). These were included in the final analysis  [SD] duration of follow up was 298 (61) days / child. A total of 24,024 morbidity episodes were reported during the home visits. Of these, 9.7% (2324/24024) were episodes of ‘presumed’ malaria. The rest of the morbidity episodes were due to: acute respiratory infections (ARI), 55.6% ; diarrhea, 33.6% (8083/24024); and minor conditions, 1.1% (257/24024).Overall, the mean (SD) incidence of all illnesses combined was 14.8 (6.8) episodes per child year. The mean (SD) incidence of ‘presumed’ malaria was 1.4 (2.0) episodes per child year. The mean (SD) incidence of ARI was 8.3 (5.0) episodes per child year and the mean (SD) incidence of diarrhea was 4.6 (10.1) episodes per child year. The longitudinal prevalences of common childhood symptoms  from age 6 to 18 mo were: 7.5%; 3.4%; and 11.7%, respectively.During the 12-mo follow up period, 39.0% (787/2016) of the children did not report any episode of ‘presumed’ malaria, 30.3% (611/2016) reported one episode and 30.7% (618/2016) reported > 1 malaria episodes. The children who reported > 1 malaria episodes were responsible for 73.7% (1713/2324) of all ‘presumed’ malaria episodes reported in the two studies.At age 18 mo, the mean (SD) length-for-age z-scores (LAZ), weight-for-age z-scores (WAZ) and weight-for-length (WLZ) scores were − 1.8 (1.1), − 1.0 (1.1) and − 0.2 (1.1) respectively. The proportions of children who were stunted, underweight and wasted were 41.5, 16.6 and 5.0%, respectively. The median  zinc protoporphyrin (ZPP) concentration was 74  μmole/mole heme and the proportion with iron deficiency was 54.1%. The mean (SD) hemogobin (Hb) concentration was 108.5 (15.1) g/L and the proportion with anemia was 50.5%. The mean (SD) scores for fine motor, gross motor, language and Profile of Social and Emotional Development (PSED) were 20.9 (2.2), 17.3 (2.6), 26.2 (5.0) and 16.2 (5.4) respectively.p = 0.069) (Table The mean (SD) change in LAZ from age 6 to 18 mo was − 0.44 (0.77). In multivariate analysis, there was no association between the incidence of ‘presumed’ malaria and change in LAZ from age 6 to 18 mo, adjusted for LAZ at age 6 mo  (Table p = 0.002).The proportion of children who were stunted increased from 27.4% at age 6 mo to 41.5% at age 18 mo. In multivariate analysis, the incidence of ‘presumed’ malaria was associated with higher risk of stunting at age 18 mo, adjusted for stunting at age 6 mo  but not with hemoglobin or iron deficiency at age 18 mo , but not for the other domains of child development, adjusted for the covariates listed in the footnotes to Tables 5.The association of incidence of ‘presumed’ malaria from age 6 to 18 mo with child development was significant for PSED scores , higher risk of stunting at age 18 mo  (Table p < 0.001), and higher risk of gross motor delay  and fine motor delay  at age 18 mo , and PSED delay  . Higher incidence of ‘presumed’ malaria was also associated with lower socio-emotional scores , suggesting that children with higher malaria incidence tended to have fewer socio-emotional problems, possibly because malaria causes lethargy and inactivity which may manifest as fewer behavioral problems.Our study had several strengths: the weekly home morbidity data collection for 1 year provided comprehensive data covering periods of both high and low malaria transmission; the longitudinal design made it possible to correlate the malaria exposure with the outcomes and interpret the directionality of association; and pooling of data from two studies helped us draw conclusions from a large sample. Although we did not calculate post-hoc power for this analysis, with a large sample size of 2016 children and narrow confidence intervals obtained for most of the morbidity outcomes, we believe the study was powered to detect clinically meaningful associations.Our results should be interpreted with caution because we excluded children who did not have the outcomes measured at age 18 mo (26% of the sample), resulting in possible survival bias. However, this attrition rate is similar to that of other studies with a long follow up period , 10. MorAnother possible cause of bias is the presumptive diagnosis of malaria, which could lead to misclassification. There is overlap in the symptoms of malaria, diarrhea and ARI  which maOur research assistants referred the children suspected of malaria to a clinic for treatment; the active surveillance and early treatment may have helped improve the study outcomes, which may have resulted in underestimation of the associations.p-values.It is also possible that the association of malaria with stunting, anemia, and PSED scores was significant by chance due to multiple testing . HoweverThe available evidence on the association of malaria with growth and other outcomes is inconclusive. Some studies have reported significant associations of malaria with stunting, hemoglobin concentration, iron status and child development , 41–44. In the studies cited above, different exposure and outcome measures were used, which may also explain the inconsistency in the findings. For example, we defined linear growth as change in LAZ and stunting. Change in LAZ indicates the growth rate between two time-points and therefore provides more information about linear growth faltering than stunting status assessed at one time-point , 52. TheThe association of diarrhea with growth has been reported in previous studies –9. FrequWe conclude that in this population of children aged 6–18 mo living in a malaria-endemic setting, with active surveillance and early treatment, ‘presumed’ malaria is not associated with change in LAZ, hemoglobin or iron status, but could be associated with stunting and anemia. In this population, diarrhoea was more consistently associated with growth than was malaria or ARI. These findings may be different in contexts where there is no active case finding and treatment for malaria is not promptly administered.


A large proportion of malaria-infected individuals in endemic areas do not experience symptoms that prompt treatment-seeking. These asymptomatically infected individuals may retain their infections for many months during which sexual-stage parasites (gametocytes) are produced that may be transmissible to mosquitoes. Reductions in malaria transmission could be achieved by detecting and treating these infections early. This study assesses the impact of enhanced community case management (CCM) and monthly screening and treatment (MSAT) on the prevalence and transmissibility of malaria infections.This cluster-randomised trial will take place in Sapone, an area of intense, highly seasonal malaria in Burkina Faso. In total, 180 compounds will be randomised to one of three interventions: arm 1 - current standard of care with passively monitored malaria infections; arm 2 - standard of care plus enhanced CCM, comprising active weekly screening for fever, and detection and treatment of infections in fever positive individuals using conventional rapid diagnostic tests (RDTs); or arm 3 - standard of care and enhanced CCM, plus MSAT using RDTs. The study will be conducted over approximately 18 months covering two high-transmission seasons and the intervening dry season. The recruitment strategy aims to ensure that overall transmission and force of infection is not affected so we are able to continuously evaluate the impact of interventions in the context of ongoing intense malaria transmission. The main objectives of the study are to determine the impact of enhanced CCM and MSAT on the prevalence and density of parasitaemia and gametocytaemia and the transmissibility of infections. This will be achieved by molecular detection of infections in all study participants during start and end season cross-sectional surveys and routine sampling of malaria-positive individuals to assess their infectiousness to mosquitoes.The study has been reviewed and approved by the London School of Hygiene and Tropical Medicine (LSHTM) (Review number: 14724) and The Centre National de Recherche et de Formation sur le Paludisme institutional review board (IRB) (Deliberation N° 2018/000002/MS/SG/CNRFP/CIB) and Burkina Faso national medical ethics committees (Deliberation N° 2018-01-010).Findings of the study will be shared with the community via local opinion leaders and community meetings. Results may also be shared through conferences, seminars, reports, theses and peer-reviewed publications; disease occurrence data and study outcomes will be shared with the Ministry of Health. Data will be published in an online digital repository.NCT03705624. This study evaluates for the first time the impact of enhanced community case management (CCM) and monthly screening and treatment (MSAT) on the transmissibility of malaria from endemic populations to mosquitoes.The detailed examination of malaria infections, gametocyte production and infectivity to mosquitoes across two peak transmission seasons and the intervening low transmission season provides uniquely detailed information on the dynamics of parasite carriage and infectivity.Intensive monitoring of mosquito exposure in combination with repeated assessments of parasite carriage in the human population allows detailed assessments of the force of malaria infection at different time points during the peak and low transmission seasons.A limitation of this current study is that findings from this setting where malaria transmission intensity is high may not translate to areas of lower transmission intensity where the tested approaches may be used in malaria elimination efforts.The study specifically aims not to impact transmission or maximise the community effect of the interventions. Rather, the study aims to quantify the impact of enhanced CCM and MSAT on the trajectory of infections experienced by the participating individuals, gametocyte production in these infections and transmissibility to mosquitoes.Plasmodiumfalciparum infection, gametocytes develop and mature in the bone marrow and first appear in the circulation 10–12 days after asexual parasites are detected.Anopheles mosquito, male and female gametocytes activate into gametes that fertilise and ultimately render the mosquito infectious to humans. Gametocytes are present in symptomatic malaria cases and in infections not accompanied by symptoms that are severe enough to elicit treatment-seeking behaviour—so-called ‘asymptomatic infections’.Malaria continues to be a major public health problem in sub-Saharan Africa. In 2017, there were an estimated 435 000 deaths from malaria globally, 93% in sub-Saharan Africa.In this study, we evaluate the impact of two intensified diagnostic and treatment strategies on the human infectious reservoir of malaria, and compare these to the current standard of care. These diagnostic and treatment strategies aim to (1) Detect and treat symptomatic infections earlier and more comprehensively by enhanced CCM (weekly active screening for fever), and (2) Detect and treat asymptomatic malaria infections by monthly screening with point-of-care rapid diagnostic tests (RDTs) (MSAT).This study is a cluster-randomised trial to determine the impact of two interventions on parasite carriage, gametocyte carriage and infectiousness to mosquitoes. A total of 180 compounds (consisting of three to six enrolled participants) will be randomised to one of three study arms (60 compounds per arm): arm 1 - current standard of care with passively monitored malaria infections; arm 2 - standard of care plus enhanced CCM; or arm 3 - standard of care and enhanced CCM, plus monthly screening and treatment (MSAT), as detailed in Box 1Standard of care with passively monitored malaria incidence at local health facilities. Health facilities will be equipped with research staff and adequate supplies to ensure malaria diagnosis and treatment with the first-line antimalarial artemether-lumefantrine (AL) according to national guidelines.Seasonal malaria chemoprevention (SMC) in children <5 years of age implemented by the National Malaria Control Programme (monthly treatment with sulfadoxine-pyrimethamine + amodiaquine from July to October).Standard of care (as in arm 1).SMC (as in arm 1).Enhanced CCM for malaria involving weekly active screening for fever using a research-grade thermometer by a trained health worker. A measured temperature ≥37.5°C or reported fever in the last 24 hours will prompt screening with a conventional rapid diagnostic test (RDT). RDT-positive individuals will be treated with AL according to national guidelines.Standard of care (as in arms 1 and 2).SMC (as in arms 1 and 2).Enhanced CCM (as in arm 2).MSAT regardless of symptoms with a conventional RDT. Screening will be performed by research staff with 25–35 days between screening rounds; RDT-positive individuals will be treated with AL according to national guidelines.The study will take place over approximately 18 months covering two high-transmission seasons and the low-transmission season (dry season) in between. Throughout the study, entomological monitoring will take place to evaluate the local mosquito population and potential exposure to infected mosquitoes.The aim of the study is to determine the ability of the interventions to detect malaria infections, and the transmission potential of these infections. To maximise coverage and ensure good adherence to intervention protocols the study will be implemented in two phases . Phase IP. falciparum) with peak transmission from approximately June to October. Asexual parasite prevalence by microscopy in this population is ~50% in children below 15 years of ageThis study will be conducted within the Saponé health and demographic surveillance system (HDSS) area, located 45 km south-west of Ouagadougou, Burkina Faso. This HDSS is part of the INDEPTH Network  and covers a total population of 85 000 living in 10 841 compounds. Compounds are georeferenced and a census of the population is conducted annually. The population is served by 23 local health facilities and a district hospital. This is a region of intense and highly seasonal malaria transmission , so that each compound will provide three to six enrolled participants. All participants must be willing to use the designated local health facilities, and to accommodate indoor and outdoor mosquito sampling for the study duration. Inclusion and exclusion criteria for individual study participants are listed in Box 2Participants should be permanent residents of the compound.Participants should be willing to participate in repeated assessments of health and infection status and willing to donate a maximum of 37 mL of blood (children <10 years of age) or 52 mL of blood  during an 18-month period.Any (chronic) illness that would affect study participation.Pre-existing severe chronic health conditions.Current participation in malaria vaccine trials or participation in such trials in the last 2 years.History of intolerance to artemether-lumefantrine.P. falciparum and/or P. vivax, P. ovalae and P. malariae) and treatment will be offered as per national guidelines. Routine surveys will be conducted throughout the wet and dry seasons to assess parasite carriage, gametocyte carriage and infectivity to mosquitoes. These surveys will be performed on a subset of compounds each week on a rolling basis, so that each compound will be visited every 10 weeks. Finger prick blood samples will be taken and processed as detailed in P. falciparum parasitaemia by quantitative PCR (qPCR) targeting varATS.At the start and end of each season, a cross-sectional survey will be performed concurrently in all enrolled compounds . These s10.1136/bmjopen-2019-030598.supp1Supplementary dataIn all three arms, clinical malaria episodes will be passively monitored at the local health facilities. Participants will be identified using study identity cards; for suspected malaria cases, temperature and clinical history will be recorded. Finger prick blood samples will be taken as detailed in Detailed assessments of mosquito exposure will be performed at the compound level. Mosquito exposure will primarily be determined using a CDC miniature light trap  placed inside one of the sleeping spaces close to the participants sleeping under a net. Sampling will be performed in every compound once every 14 days, throughout the study. To explore outdoor biting and enable more sensitive sampling of sparse mosquito populations, human landing catches will be performed indoors and outdoors from dusk until dawn for a subset of compounds.Anopheles caught in CDC traps will be determined using circumsporozoite ELISACollected mosquitoes will be sorted and counted by sex and species using morphological characteristics, and classified according to blood feeding status and parity  by microscopy. A subset of mosquitoes will be preserved for further molecular analysis.Anopleles coluzzii mosquitoes, as described previously.DMFAs will be performed to determine infectivity to locally reared female Parasite DNA and RNA will be extracted from whole blood samples collected in EDTA tubes. Parasitaemia will be assessed using a qPCR assay targeting the var gene acidic terminal sequence (varATS qPCR)Red blood cell polymorphisms that are associated with the likelihood of developing blood-stage  malaria infection, the severity of malaria infection or gametocyte production The overall aim of the study is to determine the impact of the two diagnostic strategies on prevalence and transmissibility of infections. The hypothesis is that the parasite prevalence and density are reduced in arms 2 and 3 compared with the standard of care. More infections will be detected early and may therefore be abrogated before they develop into chronic asymptomatic infections with continuous gametocytaemia. As such the primary end point is parasite prevalence and density in each arm by molecular detection in the end of study cross-sectional survey. Secondary objectives and end points seek to evaluate the impact of the interventions after each season, and to define the contribution and infectivity of gametocytes in these infections, as detailed in Box 3Parasite prevalence and density between arms by molecular detection at the end of the study cross-sectional survey ).Parasite prevalence and density by molecular detection at the end of year 1 cross-sectional survey ).Parasite prevalence and density by molecular detection at the end of the dry season cross-sectional survey ).Gametocyte prevalence and/or density by molecular methods at the end of study cross-sectional survey ).Gametocyte prevalence and/or density by molecular methods at the end of year 1 cross-sectional survey ).Gametocyte prevalence and/or density by molecular methods at the end of the dry season cross-sectional survey ).Plasmodium falciparum infections during all visits in the study .Gametocyte prevalence and/or density by molecular methods among The number of incident infections/clinical incidence detected during community case management involving active weekly fever screening, monthly screening and treatment, and passive case detection .P. falciparum infections .Infectivity to mosquitoes of The detectability of infections by highly sensitive rapid diagnostic tests .The relationship between the proportion of infected mosquitoes and gametocyte density .The impact of infection characteristics on the transmissibility of infections to mosquitoes .The impact of human host characteristics on the transmissibility of infections to mosquitoes .Association between total parasite density and gametocyte density .Malaria transmission potential based on measured gametocyte densities and the association between gametocyte density and mosquito infection rates .Number of acquired clones based on genotyping .The duration of infections in the dry season .To quantify mosquito exposure in relation to incident infections and transmission opportunities .For primary and secondary end points, parasite and gametocyte prevalences will be compared between arms using multivariate mixed-effects logistic regression models; parasite and gametocyte density will be assessed using multivariate mixed-effects linear regression models on log-transformed values. The number of incident infections will be assessed by Poisson regression and compared between arms. The proportion of infectious participants and proportion of infected mosquitoes will be assessed by logistic regression models. Analyses will take account of correlation of outcomes at the compound level and the matched randomisation scheme. There may be issues with convergence in mixed-effects models given the small number of subjects per compound. In this case, analysis based on compound level summaries will be performed. For exploratory end points, detected infections will be analysed in relation to the time and duration of infection, parasite and gametocyte prevalence and density, symptoms, complexity of infection, host characteristics, mosquito exposure and infectiousness to mosquitoes. Parasite density will be related to detectability by HS-RDTs. The association between gametocyte density and mosquito infection prevalence and intensity will be determined using an established Bayesian hierarchical model that incorporates the density of male gametocytes and gametocyte sex ratio.The hypothesis of the current study is that the parasite prevalence is considerably reduced in arms 2 and 3 compared with the standard of care. Assuming a conservative parasite prevalence of 40% in the control arm, the current sample size should be sufficient to detect a twofold reduction in parasite prevalence with >99% power. This sample size will also allow us to detect the anticipated difference in the proportion of infections that are gametocyte-positive at the moment of detection (secondary objectives 3–5). We assume that ≥80% of all infections detected in cross-sectional surveys  concurrently carry gametocytes.Anopheles gambiae mosquitoes with 65% anthropophily and 90% indoor feeding. All grid cells had the same seasonality and transmission intensity. For the simulations, the number of individuals per arm was ~165 during phase I until January 2019 when numbers increased by ~200 individuals per arm for phase II. Means of 500 stochastic realisations are shown. Simulated interventions are as follows:Simulations predict that enhanced CCM will reduce asexual parasite carriage in arm 2 by 70%, 60% and 30% in children under 5 years, 5–15 years and adults >15 years, respectively. The addition of MSAT in arm 3 is predicted to have minimal impact in all age groups . SimulatSMC: Administration of a curative drug with prophylactic protection for 30 days to children<5 years. Four rounds of SMC carried out each year starting June 30 with 30 days between rounds. Coverage was set at 80% per round and independent between rounds.ITNs: Estimated age dependent distribution; 0–5 years=67%, 5–10 years=74%, 10–15 years=68%, 15–20 years=65%, and >20 years=71%.Passive case detection and health-seeking behaviour: AL administered to uncomplicated and severe malaria cases with age-dependent distance-based health-seeking. Distances to the two study health facilities in Sapone and Pissy were calculated from the centre of each grid cell with exponential half-distance in coverage of 10 km. Maximum coverage was 50% for children under 5 years, 30% for individuals over 5 years and 80% for severe cases. Patients received treatment within 3 days of onset of clinical symptoms.EnhancedCCMin arms 2 and 3: Modelled as continuous weekly active screening where fevers of 37.5°C or higher receive AL, beginning 30 June 2018 with 100% coverage.MSAT with RDT in arm 3: Modelled as continuous monthly RDT testing , with RDT-positive individuals receiving AL, beginning 30 June 2018 with 100% coverage.Patients and the public were not involved in the design of this study. The findings of the study will be shared with the community via the local opinion leaders. The project is followed by a community meeting to present some of the preliminary findings. Disease occurrence data will be shared periodically with the Ministry of Health and we will work closely with the National Malaria Control Programme. The results may also be shared in conferences, seminars, reports, theses and peer-reviewed publications.The purpose of the study and practical consequences of participation will be explained during both community meetings and visits to each household by experienced nurses. Objectives and procedures will be explained verbally and given in printed form in French or a local language. All compound members will be screened by a good clinical practice (GCP)-trained clinician for enrolment criteria, signs of acute disease, and individual informed consent obtained . Malaria infections will not be cleared prior to inclusion in the study but this may be considered later based on results of the first season. Payment will not be given for participation but instead participants will receive financial compensation for travel and time. In addition, each participant enrolled in the study will receive a free long-lasting insecticide-treated bed net and treatment for malaria and other common illnesses free of charge. The blood draw volumes will be minimised: a maximum of 6 mL of blood will be taken at any single time point and the total volume of blood taken during a 6-month period will be lower than 37 mL for individuals enrolled in arm 3, or lower than 22 mL for those in arms 1 and 2. Both the cumulative blood draw volume and maximum blood volume taken in a single sample are within the limits considered as physiological ‘minimal risk’.This study will comply with GCP guidelines and be conducted in accordance with the latest South African revision of the Declaration of Helsinki and local regulatory requirements. All study staff will receive a local workshop on GCP before the study starts. Since no experimental treatment is used in the study a data safety and monitoring committee will not be installed; a scientific steering committee will provide technical oversight and will assist with interpretation of data. The London School of Hygiene and Tropical Medicine (LSHTM) is the research sponsor, taking responsibility for the initiation and management of the clinical trial including trial monitoring. The LSHTM Research Governance and Integrity Office has reviewed, assessed and registered the trial and holds Public Liability (‘negligent harm’) and Clinical Trial (‘non-negligent harm’) insurance policies which apply to this trial.Periodically, a subset of compounds will be randomly selected from each arm to be visited by the quality control team to monitor study implementation adherence and unintended effects of study interventions or conduct. Quality control for mosquito-feeding assays includes regular enrolment of microscopy-positive gametocyte carriers as controls. For this, children aged 10–15 years from non-participating compounds will be screened for the presence of gametocytes by microscopy and up to five gametocyte carriers will be enrolled every 6 weeks. Specific informed consent will be provided for this.