During a trial of preventive chemotherapy strategies, a hotspot of Schistosoma mansoni infection was found. Significant differences between hotspot and nonhotspot villages were found after 1 year. Villages meeting endpoints at year 5 were predicted from prior data with accuracy.

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Abstract. Schistosomiasis control programs aim to reduce morbidity but are evaluated by infection prevalence and intensity reduction. We present baseline cross-sectional data from a nested cohort study comparing indicators of morbidity for measuring program impact. Eight hundred twenty-two schoolchildren 7-8 years of age from Nyanza Province, Kenya, contributed stool for diagnosis of Schistosoma mansoni and soil-transmitted helminths (STH) and blood smears for malaria, and were evaluated for anemia, quality of life, exercise tolerance, anthropometry, and ultrasound abnormalities. Schistosoma mansoni, STH, and malaria infection prevalence were 69%, 25%, and 8%, respectively. Only anemia and S. mansoni infection (adjusted odds ratio [aOR] = 1.70; confidence interval [CI] = 1.03-2.80), and hepatomegaly and heavy S. mansoni infection (aOR = 2.21; CI = 1.19-4.11) were associated. Though anemia and hepatomegaly appeared most useful at baseline, additional morbidity indicators may be sensitive longitudinal measures to evaluate schistosomiasis program health impact.

Abstract. Compliance with mass drug administration (MDA) can be affected by rumors and mistrust about the drug. Communication campaigns are an effective way to influence attitudes and health behaviors in diverse public health contexts, but there is very little documentation about experiences using health communications in schistosomiasis control programs. A qualitative study was conducted with community health workers (CHWs) as informants to explore the effect of a health communication campaign on their experiences during subsequent praziquantel MDA for schistosomiasis. Discussions were audio-recorded, transcribed verbatim, translated into English where applicable, and analyzed thematically using ATLAS.ti software. According to the CHWs, exposure to mass media messages improved awareness of the MDA, which in turn, led to better treatment compliance. Our findings suggest that communication campaigns influence health behaviors and create awareness of schistosomiasis control interventions, which may ultimately improve praziquantel MDA.

BackgroundSchistosomiasis studies in western Kenya have mainly focused on the intestinal form, with evidence of urinary schistosomiasis remaining anecdotal. Detailed disease mapping has been carried out predominantly along the shores of Lake Victoria, but there is a paucity of information on intestinal and urinary schistosomiasis in inland sites.MethodsThis cross-sectional survey of 3,487 children aged 7–18 years from 95 schools in south Nyanza, western Kenya determined the prevalence, infection intensity, and geographical distribution of Schistosoma haematobium, evaluating its co-endemicity with Schistosoma mansoni and soil-transmitted helminths (STHs). Helminth eggs were analyzed from single urine (for S. haematobium) and stool (for S. mansoni and STHs) samples by centrifugation and Kato-Katz, respectively. Hematuria was used as a proxy indicator for S. haematobium. Schools and water bodies (ponds, water-points, streams, dams and rivers) were mapped using Geographical Information System and prevalence maps obtained using ArcView GIS Software.ResultsS. haematobium infections with an overall prevalence of 9.3% (95% CI = 8.4-10.2%) were mostly prevalent in Rachuonyo, 22.4% (95% CI = 19.2-25.9% and 19.7 eggs/10 ml) and Migori, 10.7% (95% CI = 9.2-12.3% and 29.5 eggs/10 ml) districts, particularly around Kayuka pond and Ongoche river respectively. Overall infections correlated with hematuria (r = 0.9, P < 0.0001) and were more likely in boys (P < 0.0001, OR = 0.624). S. mansoni infections with an overall prevalence of 13% (95% CI =11.9-14.1%) were majorly confined along the shores of Lake Victoria. STH infections were homogenously distributed with A. lumbricoides occurring in 5.4% (95% CI = 4.7-6.3%) and T. trichiura in 2.8% (95% CI = 2.3-3.4%) of the children. Although S. mansoni infections were more co-endemic with S. haematobium, only A. lumbricoides infections were positively associated with S. haematobium (P = 0.0295, OR = 0.4585). Overall prevalence of S. haematobium monoinfection was 7.2% (95% CI = 6.4-8%), S. mansoni monoinfection was 12.3% (95% CI = 10.4-12.5%), and S. haematobium-S. mansoni coinfection was 1.2% (95% CI = 0.9-1.6%). There was no significant difference in infection intensity between mono and coinfections.ConclusionPrevalence distribution maps obtained are important for planning and implementing disease control programs in these areas.

BackgroundSince 2011, cohorts of schoolchildren in regions bordering Lake Victoria in Kenya and Tanzania have been investigated for morbidity caused by Schistosoma mansoni infection. Despite being neighbouring countries with similar lifestyles and ecological environments, Tanzanian schoolchildren had lower S. mansoni prevalence and intensity and they were taller and heavier, fewer were wasted and anaemic, and more were physical fit compared to their Kenyan peers. The aim of the present study was to evaluate whether diet and school-related markers of socioeconomic status (SES) could explain differences in morbidity beyond the effect of infection levels.Methods and principal findingsParasitological and morbidity data from surveys in 2013–2014 were compared with information on diet and school-related markers of SES collected in 2015 using questionnaires. A total of 490 schoolchildren (163 Kenyans and 327 Tanzanians) aged 9–11 years provided data. A higher proportion of Tanzanian pupils (69.4%, 95% CI: 64.3–74.5) knew where to wash hands after toilet visits compared to Kenyan pupils (48.5%, 95% CI: 40.9–56.1; P<0.0005). Similar proportions of children in the two countries ate breakfast, lunch and dinner, but the content of the meals differed. At all three meals, a higher proportion (95% CI) of Tanzanian pupils consumed animal proteins (mostly fish proteins) compared to their Kenyan peers (35.0% (28.3–41.7) vs. 0%; P<0.0005 at breakfast; 69.0% (63.9–74.1) vs. 43.6% (35.8–51.4); P<0.0005 at lunch; and 67.2% (62.1–72.3) vs. 53.4% (45.8–61.0); P = 0.003 at dinner). Multivariable analyses investigating risk factors for important morbidity markers among individuals revealed that after controlling for schistosome and malaria infections, eating animal proteins (fish) and knowing where to wash hands after toilet visits were significant predictors for both haemoglobin levels and physical fitness (measured as VO2 max).ConclusionsThese results suggest that the differences in morbidity may be affected by factors other than S. mansoni infection alone. Diet and hygiene practice differences were associated with health status of schoolchildren along Lake Victoria in Kenya and Tanzania.Trial registrationTrials Registration numbers: ISRCT 16755535 (Kenya), ISRCT 95819193 (Tanzania).

Abstract. World Health Organization recommendations for the timing and target population for mass drug administration (MDA) for schistosomiasis are based on the prevalence of infection in school children within a given community. In a large study comparing MDA approaches for Schistosoma mansoni control, we evaluated whether prevalence of infection and egg burdens in 9-to 12-year-old students reflected infection levels in young children and adults in the same community. Cross-sectional surveys of preadolescents (9-12 years old) were compared with those of first year students (5-8 years old) in 225 villages and adults (20-55 years old) in 150 villages along the Kenyan shores of Lake Victoria. Village schistosomiasis prevalence and intensity levels in preadolescents strongly correlated (P < 0.0001) with prevalence and infection intensity for other age groups in the community. Our findings suggest that S. mansoni prevalence and intensity among 9-to 12-year-olds are valid for community sampling purposes in mapping for MDAs.

Preventive chemotherapy through mass drug administration (MDA) to control and eliminate neglected tropical diseases (NTDs) requires the active participation of communities living with NTDs, or at risk of NTD infections. Despite considerable progress by national control and elimination programs, achieving consistent and sustainable treatment campaigns that reach pastoralist communities remains challenging, which in turn delays the achievement of global disease elimination goals. The challenges of accessing pastoralist communities for treatment also hinder the achievement of the UN’s Sustainable Development Goals’ (SDGs) pledge to “leave no one behind“. Elimination targets cannot be achieved if significant proportions of endemic populations, such as pastoralists, are missed out during treatment campaigns. In South Sudan, close to 70% of the population is categorized as pastoralist, with previous data on MDA showing low access to and acceptance of MDA among the pastoralist community, as well as inconsistent treatment coverage. To address this challenge, a cross-sectional study design was conducted in five counties, with 239 pastoralist community respondents participating in in-depth interviews (IDIs), key informant interviews (KIIs), and focus group discussions (FGDs). Our findings show that, in the pastoralist community, high mobility, lay perceptions about the causes of NTDs and methods of treating them, limited awareness of MDA, and suboptimal health-seeking behaviors are the major factors that limit accessibility and participation. Our results suggest that improved uptake of MDA in these communities may be achieved by timing treatment campaigns to take account of pastoralists’ seasonal migration patterns, by involving pastoralist leaders in planning and social mobilization activities, by engaging community members as community drug distributors (CDDs), by using participatory behavior change approaches to design NTD interventions, and by addressing negative perceptions around the medicines involved, including those related to drug expiry and drugs causing impotence or other side effects. The results from this study could enable national programs to address the challenges of implementing treatment campaigns through the enhanced involvement and representation of pastoralist communities.