title: Association of community sanitation usage with soil-transmitted helminth infections among school-aged children in Amhara Region, Ethiopia.
abstract: Globally, in 2010, approximately 1.5 billion people were infected with at least one species of soil-transmitted helminth (STH), Ascaris lumbricoides, Trichuris trichiura, hookworm (Ancylostoma duodenale and Necator americanus). Infection occurs through ingestion or contact (hookworm) with eggs or larvae in the environment from fecal contamination. To control these infections, the World Health Organization recommends periodic mass treatment of at-risk populations with deworming drugs. Prevention of these infections typically relies on improved excreta containment and disposal. Most evidence of the relationship between sanitation and STH has focused on household-level access or usage, rather than community-level sanitation usage. We examined the association between the proportion of households in a community with latrines in use and prevalence of STH infections among school-aged children.
  
  
  
  Data on STH prevalence and household latrine usage were obtained during four population-based, cross-sectional surveys conducted between 2011 and 2014 in Amhara, Ethiopia. Multilevel regression was used to estimate the association between the proportion of households in the community with latrines in use and presence of STH infection, indicated by > 0 eggs in stool samples from children 6-15 years old.
  
  
  
  Prevalence of STH infection was estimated as 22% (95% CI: 20-24%), 14% (95% CI: 13-16%), and 4% (95% CI: 4-5%) for hookworm, A. lumbricoides, and T. trichiura, respectively. Adjusting for individual, household, and community characteristics, hookworm prevalence was not associated with community sanitation usage. Trichuris trichuria prevalence was higher in communities with sanitation usage ≥ 60% versus sanitation usage < 20%. Association of community sanitation usage with A. lumbricoides prevalence depended on household sanitation. Community sanitation usage was not associated with A. lumbricoides prevalence among households with latrines in use. Among households without latrines in use, A. lumbricoides prevalence was higher comparing communities with sanitation usage ≥ 60% versus < 20%. Households with a latrine in use had lower prevalence of A. lumbricoides compared to households without latrines in use only in communities where sanitation usage was ≥ 80%.
  
  
  
  We found no evidence of a protective association between community sanitation usage and STH infection. The relationship between STH infection and community sanitation usage may be complex and requires further study.
authors.affiliation: Department of Disease Control, London School of Hygiene and Tropical Medicine, London, UK. william.oswald@lshtm.ac.uk.|Department of Epidemiology, Emory University, Atlanta, GA, USA. william.oswald@lshtm.ac.uk.
authors.forename: William E
authors.initials: WE
authors.lastname: Oswald
authors.affiliation: The Carter Center, Atlanta, GA, USA.
authors.forename: Aisha E P
authors.initials: AE
authors.lastname: Stewart
authors.affiliation: Department of Epidemiology, Emory University, Atlanta, GA, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Kramer
authors.affiliation: The Carter Center, Addis Ababa, Ethiopia.
authors.forename: Tekola
authors.initials: T
authors.lastname: Endeshaw
authors.affiliation: The Carter Center, Addis Ababa, Ethiopia.
authors.forename: Mulat
authors.initials: M
authors.lastname: Zerihun
authors.affiliation: The Carter Center, Addis Ababa, Ethiopia.
authors.forename: Berhanu
authors.initials: B
authors.lastname: Melak
authors.affiliation: The Carter Center, Addis Ababa, Ethiopia.
authors.forename: Eshetu
authors.initials: E
authors.lastname: Sata
authors.affiliation: The Carter Center, Addis Ababa, Ethiopia.
authors.forename: Demelash
authors.initials: D
authors.lastname: Gessese
authors.affiliation: The Carter Center, Addis Ababa, Ethiopia.
authors.forename: Tesfaye
authors.initials: T
authors.lastname: Teferi
authors.affiliation: The Carter Center, Addis Ababa, Ethiopia.
authors.forename: Zerihun
authors.initials: Z
authors.lastname: Tadesse
authors.affiliation: Amhara Regional Health Bureau, Bahir Dar, Ethiopia.
authors.forename: Birhan
authors.initials: B
authors.lastname: Guadie
authors.affiliation: The Carter Center, Atlanta, GA, USA.|World Health Organization, Geneva, Switzerland.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: King
authors.affiliation: The Carter Center, Atlanta, GA, USA.|International Trachoma Initiative, Atlanta, GA, USA.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Emerson
authors.affiliation: The Carter Center, Atlanta, GA, USA.
authors.forename: Elizabeth K
authors.initials: EK
authors.lastname: Callahan
authors.affiliation: Department of Environmental Health, Emory University, Atlanta, GA, USA.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Freeman
authors.affiliation: Department of Epidemiology, Emory University, Atlanta, GA, USA.
authors.forename: W Dana
authors.initials: WD
authors.lastname: Flanders
authors.affiliation: Department of Environmental Health, Emory University, Atlanta, GA, USA.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Clasen
authors.affiliation: Hubert Department of Global Health and Center for Global Safe Water, Sanitation, and Hygiene, Emory University, Atlanta, GA, USA.
authors.forename: Christine L
authors.initials: CL
authors.lastname: Moe
mesh_terms: D000293:Adolescent; D000723:Ancylostomatoidea / Q000302:isolation & purification; D000818:Animals; D001196:Ascariasis / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission; D017164:Ascaris lumbricoides / Q000302:isolation & purification; D002648:Child; D003430:Cross-Sectional Studies; D005002:Ethiopia / Q000453:epidemiology; D005191:Family Characteristics; D005243:Feces / Q000469:parasitology; D005260:Female; D006376:Helminths / Q000302:isolation & purification; D006725:Hookworm Infections / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission; D006801:Humans; D008297:Male; D015995:Prevalence; D012499:Sanitation; D012987:Soil / Q000469:parasitology*; D011795:Surveys and Questionnaires; D014038:Toilet Facilities; D014257:Trichuriasis / Q000453:epidemiology* / Q000469:parasitology / Q000635:transmission*; D014258:Trichuris / Q000302:isolation & purification
chemical_list: D012987:Soil
keywords: Ethiopia; Sanitation; Soil-transmitted helminths