Baseline prevalence and intensity of schistosomiasis at sentinel sites in Madagascar: Informing a national control strategy

Background: schistosomiasis affects more than 800 million people,mostly in sub-saharan africa. a baseline sentinel site study was conducted in the western half of madagascar to determine the prevalence and intensity of schistosomiasis and soil-transmitted helminth (sth) infections prior to mass drug administration,and to explore the associations between infection and school attendance,and access to water,sanitation and hygiene (wash) facilities. methods: a three-stage,cluster-randomised cross-sectional study was conducted in 29 sentinel sites in october 2015. twenty school attending and 4 non-attending children in each of the age groups from 7 to 10 years old were randomly selected at each site for detection of schistosoma haematobium eggs in a single urine slide by filtration,and of s. mansoni,ascaris lumbricoides,trichuris trichiura and hookworm eggs in duplicate kato-katz slides from a single stool sample. school attendance was registered individually,and school-level access to wash facilities was scored through pre-defined observed and reported factors. logistic regression analysis was performed,adjusting for gender,age and study site. school-level wash status was analysed using spearman's rank correlation coefficient. results: a total of 1,958 children were included. the prevalence of s. haematobium infection and heavy-intensity infection was 30.5 % and 15.1 %,respectively. the prevalence of s. mansoni infection and heavy-intensity infection was 5.0 % and 0.9 %,respectively. the prevalence of any sth infection was 4.7 %. there was no significant difference in prevalence of infection or heavy-intensity infection of either schistosome species between attending and non-attending children,apart from heavy-intensity s. mansoni infection that was significantly more common in children who did not attend school regularly (aor=7.5 (95 % ci=1.1-49.5); p=0.037). only a minority of schools had adequate access to wash facilities,and in this study,we found no significant association between school-level wash status and schistosomiasis. conclusions: this study found an alarmingly high prevalence and intensity of schistosomiasis,and the results warrant urgent scale-up of the national ntd control programme that will need to include both non-attending and attending school-age children in order to reach who roadmap targets for the control of schistosomiasis by 2020. © 2016 rasoamanamihaja et al.