Sickle cell trait (HbAS) and stunting in children below two years of age in an area of high malaria transmission

<p>Abstract</p> <p>Background</p> <p>While the protective effects of sickle cell trait (HbAS) against severe malaria and the resulting survival advantage are well known, the impact on the physical development in young children remains unclear. This study was aimed to investigate the relationship between HbS carriage and stunting in children below two years of age in a cohort from the Ashanti Region, Ghana.</p> <p>Methods</p> <p>1,070 children were recruited at three months of age and followed-up for 21 months with anthropometric measurements performed every three months. Incidence rate ratios with 95% confidence intervals were calculated by Poisson regression to estimate the association of β-globin genotypes with the number of malaria episodes. Odds ratios (OR) were calculated for the association between the occurrence of β-globin genotypes and/or malaria episodes and stunting. The age-dependent between-group and within-group effects for the β-globin genotypes were assessed by population-averaged models estimated by generalized estimation equation with autoregressive correlation structure.</p> <p>Results</p> <p>Analyses showed a significantly lower age-dependent risk of stunting (OR 0.56; 95% CI 0.33–0.96) in carriers of the HbAS genotype (n = 102) in comparison to those with HbAA (n = 692). This effect was restricted to children who experienced malaria episodes during the observation period suggesting that the beneficial effect of the β-globin HbS variant on the incidence of stunting is closely linked to its protection from mild malaria episodes.</p> <p>Conclusion</p> <p>The lower risk of chronic malnutrition in early childhood, mediated by protection against mild malaria episodes, may contribute to the survival advantage of HbAS carriers in areas of high malaria transmission.</p

Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi).

BACKGROUND: Intermittent preventive antimalarial treatment in infants (IPTi) is currently evaluated as a malaria control strategy. Among the factors influencing the extent of protection that is provided by IPTi are the transmission intensity, seasonality, drug resistance patterns, and the schedule of IPTi administrations. The aim of this study was to determine how far the protective efficacy of IPTi depends on spatio-temporal variations of the prevailing incidence of malaria. METHODS: One thousand seventy infants were enrolled in a registered controlled trial on the efficacy of IPTi with sulphadoxine-pyrimethamine (SP) in the Ashanti Region, Ghana, West Africa (ClinicalTrial.gov: NCT00206739). Stratification for the village of residence and the month of birth of study participants demonstrated that the malaria incidence was dependent on spatial (range of incidence rates in different villages 0.6-2.0 episodes/year) and temporal (range of incidence rates in children of different birth months 0.8-1.2 episodes/year) factors. The range of spatio-temporal variation allowed ecological analyses of the correlation between malaria incidence rates, anti-Plasmodium falciparum lysate IgG antibody levels and protective efficacies provided by IPTi. RESULTS: Protective efficacy of the first SP administration was positively correlated with malaria incidences in children living in a distinct village or born in a distinct month (R2 0.48, p < 0.04 and R2 0.63, p < 0.003, respectively). Corresponding trends were seen after the second and third study drug administration. Accordingly, IgG levels against parasite lysate increased with malaria incidence. This correlation was stronger in children who received IPTi, indicating an effect modification of the intervention. CONCLUSION: The spatial and temporal variations of malaria incidences in a geographically and meteorologically homogeneous study area exemplify the need for close monitoring of local incidence rates in all types of intervention studies. The increase of the protective efficacy of IPTi with malaria incidences may be relevant for IPTi implementation strategies and, possibly, for other malaria control measures

Microbiological screenings for infection control in unaccompanied minor refugees: the German Armed Forces Medical Service’s experience

Abstract Background The German Military Medical Service contributed to the medical screening of unaccompanied minor refugees (UMRs) coming to Germany in 2014 and 2015. In this study, a broad range of diagnostic procedures was applied to identify microorganisms with clinical or public health significance. Previously, those tests had only been used to screen soldiers returning from tropical deployments. This instance is the first time the approach has been studied in a humanitarian context. Methods The offered screenings included blood cell counts, hepatitis B serology and microscopy of the stool to look for protozoa and worm eggs as well as PCR from stool samples targeting pathogenic bacteria, protozoa and helminths. If individuals refused certain assessments, their decision to do so was accepted. A total of 219 apparently healthy male UMRs coming from Afghanistan, Egypt, Somalia, Eritrea, Syria, Ghana, Guinea, Iran, Algeria, Iraq, Benin, Gambia, Libya, Morocco, Pakistan, and Palestine were assessed. All UMRs who were examined at the study department were included in the assessment. Results We detected decreasing frequencies of pathogens that included diarrhoea-associated bacteria [Campylobacter (C.) jejuni, enteropathogenic Escherichia (E.) coli (EPEC), enterotoxic E. coli (ETEC), enteroaggregative E. coli (EAEC), enteroinvasive E. coli (EIEC)/Shigella spp.), Giardia (G.) duodenalis, helminths (comprising Schistosoma spp., Hymenolepis (H.) nana, Strongyloides (S.) stercoralis] as well as hepatitis B virus. Pathogenic microorganisms dominated the samples by far. While G. duodenalis was detected in 11.4% of the assessed UMRs, the incidence of newly identified cases in the German population was 4.5 cases per 100,000 inhabitants. Conclusions We conclude that the applied in-house PCR screening systems, which have proven to be useful for screening military returnees from tropical deployments, can also be used for health assessment of immigrants from the respective sites. Apparently healthy UMRs may be enterically colonized with a broad variety of pathogenic and apathogenic microorganisms. Increased colonization rates, as shown for G. duodenalis, can pose a hygiene problem in centralized homes for asylum seekers

Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi)-3

<p><b>Copyright information:</b></p><p>Taken from "Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi)"</p><p>http://www.malariajournal.com/content/6/1/163</p><p>Malaria Journal 2007;6():163-163.</p><p>Published online 9 Dec 2007</p><p>PMCID:PMC2234423.</p><p></p>the respective study arm in each village. A, stratified by month of birth (Wald test, p = 0.118). B, stratified by village of residence (Wald test, p < 0.001). Blue circles and lines (linear regression), children from placebo arm; red diamonds and lines (linear regression), children from SP arm. PYAR, person year at risk

Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi)-0

<p><b>Copyright information:</b></p><p>Taken from "Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi)"</p><p>http://www.malariajournal.com/content/6/1/163</p><p>Malaria Journal 2007;6():163-163.</p><p>Published online 9 Dec 2007</p><p>PMCID:PMC2234423.</p><p></p>year, beginning at the time of recruitment. A, PYAR stratified for the month of birth of the children; B, PYAR stratified for the village of residence of the children. PYAR, person year at risk

Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi)-1

<p><b>Copyright information:</b></p><p>Taken from "Malaria incidence and efficacy of intermittent preventive treatment in infants (IPTi)"</p><p>http://www.malariajournal.com/content/6/1/163</p><p>Malaria Journal 2007;6():163-163.</p><p>Published online 9 Dec 2007</p><p>PMCID:PMC2234423.</p><p></p> after the drug administration (blue circles and line, after IPTi-1; red diamonds and line, after IPTi-2; green triangles and line, after IPTi-3) and malaria incidence rates per PYAR for the same time periods in the placebo arm. A, stratified by month of birth (IPTi-1, R0.63, p < 0.003; IPTi-2, R0.29, p = 0.07; IPTi-3, R0.37, p < 0.04); B, stratified by village of residence (IPTi-1, R0.48, p < 0.04; IPTi-2, R0.33, p = 0.11; IPTi-3, R0.04, p = 0.60). PYAR, person year at risk