title: Cryptosporidiosis among children in an endemic semiurban community in southern India: does a protected drinking water source decrease infection?
abstract: BACKGROUND
  A quasi-experimental study was conducted to determine whether or not a protected water supply (bottled drinking water) could prevent or delay cryptosporidial infections among children residing in an endemic community.
  
  
  METHODS
  A total of 176 children residing in a semiurban slum area in southern India were enrolled preweaning and received either bottled (n = 90) or municipal (n = 86) drinking water based on residence in specific streets. Weekly surveillance visits were conducted until children reached their second birthday. Stool samples were collected every month and during diarrheal episodes, and were tested for the presence of Cryptosporidium species by polymerase chain reaction. Differences in the incidence of cryptosporidiosis between bottled and municipal water groups were compared using Poisson survival models, and a propensity score model was developed to adjust for the effect of potential confounders.
  
  
  RESULTS
  A total of 186 episodes of cryptosporidiosis, mostly asymptomatic, were observed in 118 (67%) children during the follow-up period at a rate of 0.59 episodes per child-year. Diarrhea associated with Cryptosporidium species tended to be longer in duration and more severe. Stunting at 6 months was associated with a higher risk of cryptosporidiosis (rate ratio [RR] = 1.40; 95% confidence interval [CI], 1.03-1.91). A higher gastrointestinal disease burden was also seen in children with cryptosporidiosis. Drinking bottled water was not associated with a reduced risk of cryptosporidiosis (adjusted RR = 0.86; 95% CI, .60-1.23).
  
  
  CONCLUSIONS
  This study documented a high burden of cryptosporidiosis among children in an endemic Indian slum community. The lack of association between drinking bottled water and cryptosporidiosis suggests possible spread from asymptomatically infected individuals involving multiple transmission pathways.
authors.affiliation: Department of Gastrointestinal Sciences, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Rajiv
authors.initials: R
authors.lastname: Sarkar
authors.forename: Sitara S R
authors.initials: SS
authors.lastname: Ajjampur
authors.forename: Ashok D
authors.initials: AD
authors.lastname: Prabakaran
authors.forename: Jayanthy C
authors.initials: JC
authors.lastname: Geetha
authors.forename: Thuppal V
authors.initials: TV
authors.lastname: Sowmyanarayanan
authors.forename: Anne
authors.initials: A
authors.lastname: Kane
authors.forename: Joanne
authors.initials: J
authors.lastname: Duara
authors.forename: Jayaprakash
authors.initials: J
authors.lastname: Muliyil
authors.forename: Vinohar
authors.initials: V
authors.lastname: Balraj
authors.forename: Elena N
authors.initials: EN
authors.lastname: Naumova
authors.forename: Honorine
authors.initials: H
authors.lastname: Ward
authors.forename: Gagandeep
authors.initials: G
authors.lastname: Kang
mesh_terms: D002675:Child, Preschool; D003457:Cryptosporidiosis / Q000453:epidemiology* / Q000517:prevention & control*; D003458:Cryptosporidium / Q000302:isolation & purification*; D003967:Diarrhea / Q000469:parasitology; D060766:Drinking Water / Q000469:parasitology*; D019353:Endemic Diseases; D005243:Feces / Q000469:parasitology; D006801:Humans; D015994:Incidence; D007194:India / Q000453:epidemiology; D007223:Infant; D007231:Infant, Newborn; D013383:Suburban Population
chemical_list: D060766:Drinking Water
keywords: India; children; cryptosporidiosis; drinking water; quasi-experimental study