Schistosoma mansoni infection and its association with nutrition and health outcomes : a household survey in school-aged children living in Kasansa, Democratic Republic of the Congo

Introduction: schistosomiasis (SCH) is an important public health problem in developing countries and school-aged children are the most affected. This study explored health and nutritional status and their correlation with SCH in children attending primary school (3rd to 6th class) living in the area of Kasansa in the Democratic Republic of Congo. Methods: across-sectional household survey was carried out in Kasansa health area in February 2011. Children whose parents reported to attend primary school (3rd to 6th class) were included. Socio-demographic characteristics, information on morbidity history and risk factor were collected using a semi-structured questionnaire. S. mansoni and malaria infection were assessed using the Kato-katz technique and rapid diagnostic test, respectively. Haemoglobin concentration was also performed using a portable HemoControl device. Bivariate and multiple logistic regressions were used to assess risk factors for S. mansoni. Results: a total of 197 school aged children participated in the study with a median age of 12 years and 53.8% of them were boys. The overall health status of the children was poor with very high prevalences of S. mansoni infection (89.3%), malaria infection (65.1%), anaemia (61.4%) and stunting (61.0%). Regular contact with river water was the most important risk factor (OR: 11.7; p<0.001) related to SCH infection. A low haemoglobin concentration was significantly associated with a SCH infection (OR: 12.3; p=0.003) and egg load was associated with stunting (OR: 12.4; p=0.04). Children from farmers were more at risk for low school performance (OR: 5.3; p=0.03). Conclusion: high prevalence of Schistosoma mansoni and malaria infection was observed in the study population living in Kasansa area. Moreover, they presented a high burden of anaemia, chronic malnutrition and low school performance. An integrated disease control and management of these diseases and their consequences, endorsed by surveillance, is needed

High Prevalence of <i>Schistosoma mansoni</i> in Six Health Areas of – Kasansa Health Zone, Democratic Republic of the Congo: Short Report

<div><p>School-aged children suffer the most from schistosomiasis infection in sub Saharan Africa due to poverty and limited sanitary conditions. Mapping of disease burden is recommended and there is a need of updating prevalence data which is as old as 20 years in the Democratic Republic of Congo. An epidemiological and parasitological study was carried out in 2011 in the health zone of Kasansa. Six health areas (HA) were included in the study. In each health area, one primary school was selected. School-aged children were screened for <i>S. mansoni</i> infection using parallel Kato-Katz and direct microscopy techniques. A total of 335 school-aged children were screened. The average prevalence was 82.7% and ranged between 59.5–94.9%. Four of the six HAs had a prevalence level over 91%. Of all infected children, about half 112 (43.2%) had light parasite density. These results demonstrate that <i>Schistosoma mansoni</i> infection is a bigger problem than anticipated and there is an urgent need to implement effective control measures.</p></div

Prevalence of <i>S. mansoni</i> in the six health areas of Kasansa health zone.

<p>Prevalence of <i>S. mansoni</i> in the six health areas of Kasansa health zone.</p

Democratic Republic of the Congo, the province of Kasaï Oriental is highlighted.

<p>Democratic Republic of the Congo, the province of Kasaï Oriental is highlighted.</p

A High Throughput Whole Blood Assay for Analysis of Multiple Antigen-Specific T Cell Responses in Human Mycobacterium tuberculosis Infection

Antigen-specific CD4 and CD8 T cells are important components of the immune response to Mycobacterium tuberculosis, yet little information is currently known regarding how the breadth, specificity, phenotype, and function of M. tuberculosis-specific T cells correlate with M. tuberculosis infection outcome in humans. To facilitate evaluation of human M. tuberculosis-specific T cell responses targeting multiple different Ags, we sought to develop a high throughput and reproducible T cell response spectrum assay requiring low blood sample volumes. We describe here the optimization and standardization of a microtiter plate-based, diluted whole blood stimulation assay utilizing overlapping peptide pools corresponding to a functionally diverse panel of 60 M. tuberculosis Ags. Using IFN-γ production as a readout of Ag specificity, the assay can be conducted using 50 μl of blood per test condition and can be expanded to accommodate additional Ags. We evaluated the intra- and interassay variability, and implemented testing of the assay in diverse cohorts of M. tuberculosis-unexposed healthy adults, foreign-born adults with latent M. tuberculosis infection residing in the United States, and tuberculosis household contacts with latent M. tuberculosis infection in a tuberculosis-endemic setting in Kenya. The M. tuberculosis-specific T cell response spectrum assay further enhances the immunological toolkit available for evaluating M. tuberculosis-specific T cell responses across different states of M. tuberculosis infection, and can be readily implemented in resource-limited settings. Moreover, application of the assay to longitudinal cohorts will facilitate evaluation of treatment- or vaccine-induced changes in the breadth and specificity of Ag-specific T cell responses, as well as identification of M. tuberculosis-specific T cell responses associated with M. tuberculosis infection outcomes