title: A Cross-Sectional Study of Water, Sanitation, and Hygiene-Related Risk Factors for Soil-Transmitted Helminth Infection in Urban School- and Preschool-Aged Children in Kibera, Nairobi.
abstract: Soil-transmitted helminth (STH) infections affect persons living in areas with poor water, sanitation, and hygiene (WASH). Preschool-aged children (PSAC) and school-aged children (SAC) are disproportionately affected by STH infections. We aimed to identify WASH factors associated with STH infection among PSAC and SAC in Kibera, Kenya. In 2012, households containing a PSAC or SAC were randomly selected from those enrolled in the International Emerging Infections Program, a population-based surveillance system. We administered a household questionnaire, conducted environmental assessments for WASH, and tested three stools from each child for STH eggs using the Kato-Katz method. WASH factors were evaluated for associations with STH infection using univariable and multivariable Poisson regression. Any-STH prevalence was 40.8% among 201 PSAC and 40.0% among 475 SAC enrolled. Using the Joint Monitoring Programme water and sanitation classifications, 1.5% of households reported piped water on premises versus 98.5% another improved water source; 1.3% reported improved sanitation facilities, while 81.7% used shared sanitation facilities, 13.9% had unimproved facilities, and 3.1% reported no facilities (open defecation). On univariable analysis, STH infection was significantly associated with a household toilet located off-premises (prevalence ratio (PR) = 1.33; p = 0.047), while always treating water (PR = 0.81; p = 0.04), covering drinking water containers (PR = 0.75; p = 0.02), using clean towels during hand drying (PR = 0.58; p<0.01), having finished household floor material (PR = 0.76; p<0.01), having electricity (PR = 0.70; p<0.01), and increasing household elevation in 10-meter increments (PR = 0.89; p<0.01) were protective against STH infection. On multivariable analysis, usually versus always treating water was associated with increased STH prevalence (adjusted prevalence ratio (aPR) = 1.52; p<0.01), while having finished household floor material (aPR = 0.76; p = 0.03), reported child deworming in the last year (aPR = 0.76; p<0.01), and 10-meter household elevation increases (aPR = 0.89; p<0.01) were protective against infection. The intersection between WASH and STH infection is complex; site-specific WASH interventions should be considered to sustain the gains made by deworming activities.
authors.affiliation: Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Caitlin M
authors.initials: CM
authors.lastname: Worrell
authors.affiliation: Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Ryan E
authors.initials: RE
authors.lastname: Wiegand
authors.affiliation: Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Davis
authors.affiliation: Centre for Global Health Research, Kenya Medical Research Institute, Nairobi, Kenya.
authors.forename: Kennedy O
authors.initials: KO
authors.lastname: Odero
authors.affiliation: Waterborne Disease Prevention Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Anna
authors.initials: A
authors.lastname: Blackstock
authors.affiliation: Waterborne Disease Prevention Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Victoria M
authors.initials: VM
authors.lastname: Cuéllar
authors.affiliation: Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute, Nairobi, Kenya.
authors.forename: Sammy M
authors.initials: SM
authors.lastname: Njenga
authors.affiliation: Division of Global Health Protection, Centers for Disease Control and Prevention, Nairobi, Kenya.
authors.forename: Joel M
authors.initials: JM
authors.lastname: Montgomery
authors.affiliation: Waterborne Disease Prevention Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Roy
authors.affiliation: Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: LeAnne M
authors.initials: LM
authors.lastname: Fox
mesh_terms: D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006373:Helminthiasis / Q000453:epidemiology* / Q000635:transmission*; D006801:Humans; D006920:Hygiene; D007630:Kenya / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D012499:Sanitation / Q000706:statistics & numerical data*; D012574:Schools / Q000706:statistics & numerical data*; D012987:Soil / Q000469:parasitology*; D014505:Urban Population / Q000706:statistics & numerical data; D014867:Water / Q000469:parasitology*
chemical_list: D012987:Soil; D014867:Water