Spatial distribution and risk factors of Schistosoma haematobium and hookworm infections among schoolchildren in Kwale, Kenya

Abstract

BackgroundLarge-scale schistosomiasis control programs are implemented in regions with diverse social and economic environments. A key epidemiological feature of schistosomiasis is its small-scale heterogeneity. Locally profiling disease dynamics including risk factors associated with its transmission is essential for designing appropriate control programs. To determine spatial distribution of schistosomiasis and its drivers, we examined schoolchildren in Kwale, Kenya.Methodology/Principal findingsWe conducted a cross-sectional study of 368 schoolchildren from six primary schools. Soil-transmitted helminths and Schistosoma mansoni eggs in stool were evaluated by the Kato-Katz method. We measured the intensity of Schistosoma haematobium infection by urine filtration. The geometrical mean intensity of S. haematobium was 3.1 eggs/10 ml urine (school range, 1.4–9.2). The hookworm geometric mean intensity was 3.2 eggs/g feces (school range, 0–17.4). Heterogeneity in the intensity of S. haematobium and hookworm infections was evident in the study area. To identify factors associated with the intensity of helminth infections, we utilized negative binomial generalized linear mixed models. The intensity of S. haematobium infection was associated with religion and socioeconomic status (SES), while that of hookworm infection was related to SES, sex, distance to river and history of anthelmintic treatment.Conclusions/SignificanceBoth S. haematobium and hookworm infections showed micro-geographical heterogeneities in this Kwale community. To confirm and explain our observation of high S. haematobium risk among Muslims, further extensive investigations are necessary. The observed small scale clustering of the S. haematobium and hookworm infections might imply less uniform strategies even at finer scale for efficient utilization of limited resources.

Urinary schistosomosis in patients of rural medical health centers in Kwale county, Kenya

“…Our survey revealed some areas with a higher proportion of study participants infected with S. haematobium (i.e., the catchment areas of Mwachinga, Mwaluphamba and Bilashaka Dispensaries with 11.96 %, 20.96 % and 22.13 % of infected individuals, respectively), while the other locality surveyed (catchment area of Mbuwani Dispensary) showed only a very slight proportion of infected subjects (1.13 %). The focal character of schistosomosis transmission was documented by a number of relevant publications (Brooker, 2002;Clennon et al, 2006;Meurs et al, 2013;Chadeka et al, 2017), suggesting a public health problem in geographically restricted localities. The difference between men and women in the prevalence of schistosomosis was not statistically significant (17.18 % and 14.55 %, respectively; p = 0.48).…”

“…At the end of the twentieth century the prevalence of S. haematobium infection was >70% among school-aged children in Kwale County, Kenya (King et al, 1988, Sato et al, 1988. Recent publications refer that more than 30 % of schoolchildren could be infected with S. haematobium in this part of Kenya (Bustinduy, 2013, Chadeka, 2017, Njenga, 2014. In the framework of deworming programme, in Mwaluphamba, Bilashaka and Mbuwani, co-administration of praziquantel (against urinary schistosomiasis) and albendazole (against soil-transmitted helminth infections) to community and school children was performed once a year in follwoing years: 2004,2005,2007,2009 and 2012.…”

Influences of Land-Use Dynamics and Surface Water Systems Interactions on Water-Related Infectious Diseases—A Systematic Review

“…Temperature, turbidity, pH Dengue [75] Temperature Malaria [59,75,87] E. coli, fecal coliform Cholera [45,61,62,81,88] E. coli, fecal coliform, turbidity, pH Dysentery [61,62,89] E. coli, fecal coliform Typhoid fever [61,62] E. coli, fecal coliform, BOD, temperature, DO Cryptosporidiosis [70,81] Fecal coliform Schistosomiasis [76,77,83,85,[90][91][92] E. coli, fecal coliform, temperature, turbidity Buruli ulcer [85] E. coli, fecal coliform, temperature, DO, BOD, TSS, turbidity Hookworm [92] pH = Potential of Hydrogen; DO = Dissolved Oxygen; BOD = Biochemical Oxygen Demand; TSS = Total Dissolved Solid.…”

“…Lack of sanitation and hygiene facilities compelled households in remote communities in Tanzania to practice open defecation in and around water bodies, which resulted in high levels of fecal coliform concentration in the water and increased the survival rate of the intermediate snail host of Schistosoma haematobium [91]. It was argued that differences in the spatial distribution of S. haematobium are influenced by the spatial connectedness of land-use types, water pollution patterns, and risk and exposure factors [92].…”

Evaluación del riesgo de infecciones parasitarias intestinales en poblaciones infanto-juveniles de Argentina: el impacto de los factores ambientales y socio-económicos en su distribución geográfica

“…A lo largo del tiempo, la comunidad científica ha enfatizado el desarrollo de tratamientos y vacunas para el control de enfermedades. Sin embargo, en los últimos años ha profundizado el estudio sobre la distribución geográfica y por ello, la bibliografía se ha enriquecido con exitosas investigaciones realizadas principalmente en países de África (Knopp et al, 2008;Clements et al, 2010;Ouattara et al, 2010;Pullan et al, 2014;Chadeka et al, 2017), de Asia (Brooker et al, 2003;Ngui et al, 2014;Wardell et al, 2017) y de Sudamérica (Chammartin et al, 2013b(Chammartin et al, , 2014Gamboa, et al, 2014;Coronato Nunes et al, 2016;Faria et al, 2017).…”