title: Risk of giardiasis associated with water supply in an endemic context.
abstract: Consumption of untreated, inadequately treated or simply chlorinated water has been the source of a number of giardiasis epidemics. The aim of this study was to verify if water supply is associated with giardiasis in an endemic context. We conducted a case-control study that included 139 cases and 417 control subjects. To assess risk associated to water consumption, we calculated odds ratios (OR) using "source of water" and "presence and type of filtration" as criteria. A logistic regression model was used to control other risk factors. In children aged 1 - 13, the only significant risk factor was the consumption of at-risk tap water (i.e., filtered or unfiltered surface water or unfiltered shallow well water; OR = 6.13). In people aged 14 - 64, the consumption of this water was not a risk factor for the disease. The divergence in results between age groups could be explained by acquired immunity.
authors.affiliation: Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Canada. fgagnon.rr05@ssss.gouv.qc.ca
authors.forename: Fabien
authors.initials: F
authors.lastname: Gagnon
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Duchesne
authors.forename: Benoît
authors.initials: B
authors.lastname: Lévesque
authors.forename: Suzanne
authors.initials: S
authors.lastname: Gingras
authors.forename: Josée
authors.initials: J
authors.lastname: Chartrand
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D004196:Disease Outbreaks; D005260:Female; D005873:Giardiasis / Q000453:epidemiology* / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011792:Quebec; D012044:Regression Analysis; D012306:Risk; D012307:Risk Factors; D014881:Water Supply