title: Helminth infections among people using wastewater and human excreta in peri-urban agriculture and aquaculture in Hanoi, Vietnam.
abstract: OBJECTIVE
  To assess the prevalence of helminth infections and their associated risks in a community using both wastewater and human excreta in agriculture and aquaculture.
  
  
  METHODS
  A cross-sectional study was conducted in a peri-urban area in Hanoi, Vietnam. Data on the demography, socioeconomics and sanitation were collected from a survey of 400 agricultural households. Parasitological examination for the eggs of Ascaris sp., Trichuris sp. and hookworm was performed on single stool specimens obtained from study household members' 15-70 years and 0-72 months of age.
  
  
  RESULTS
  Of 807 stool samples collected from 620 adults and 187 children, 39% were infected with helminths. The prevalence of infections with Ascaris sp., Trichuris sp. and hookworm was 21.6%, 9.8% and 21.8%, respectively. Univariate and multivariate analyses showed that being an adult, female gender, living in a household without a latrine, excreta composted for less than 1 month and use of fresh human excreta were significantly associated with co-infection with all three helminths. Being an adult was an independent determinant for infections with individual helminths. The absence of a latrine and use of stored urine for irrigation were associated with an increased risk of Ascaris infection. Risk factors for Trichuris infection were inadequately composted excreta and year-round wastewater contact; risk factors for hookworm infection were female gender, household without a latrine and use of fresh human excreta.
  
  
  CONCLUSIONS
  Wastewater exposure did not pose a major risk for helminth infection in this community. Instead, lack of sanitation facilities and use of fresh or inadequately composted human excreta in agriculture were important risk factors.
authors.affiliation: Division of Enteric Infections, National Institute of Hygiene and Epidemiology, Hanoi, Vietnam. tranghai16@yahoo.com
authors.forename: Thuy Trang
authors.initials: TT
authors.lastname: Do
authors.forename: Kåre
authors.initials: K
authors.lastname: Mølbak
authors.forename: Dac Cam
authors.initials: DC
authors.lastname: Phung
authors.forename: Anders
authors.initials: A
authors.lastname: Dalsgaard
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000383:Agriculture; D000818:Animals; D017756:Aquaculture; D017164:Ascaris lumbricoides / Q000469:parasitology; D003430:Cross-Sectional Studies; D005243:Feces / Q000469:parasitology; D005260:Female; D006373:Helminthiasis / Q000175:diagnosis* / Q000469:parasitology / Q000517:prevention & control; D006725:Hookworm Infections / Q000175:diagnosis* / Q000469:parasitology / Q000517:prevention & control; D006801:Humans; D007411:Intestinal Diseases, Parasitic / Q000209:etiology; D008297:Male; D008875:Middle Aged; D012499:Sanitation / Q000592:standards*; D014201:Trematode Infections / Q000175:diagnosis* / Q000469:parasitology / Q000517:prevention & control; D014257:Trichuriasis / Q000175:diagnosis* / Q000469:parasitology / Q000517:prevention & control; D014744:Vietnam; D014871:Water Microbiology