title: Household clustering of gastroenteritis.
abstract: Surveillance for gastroenteritis rarely detects small, intra-familial outbreaks. This study examined intra-household transmission of gastroenteritis using prospectively collected data from 2811 participants (600 households) in a community-based study. There were 258 household clusters of gastroenteritis during the 15 months of observation involving 774 residents (28% of total). Age <6 years and attendance at a day care/kindergarten were associated with increased likelihood of inclusion in a cluster. The reach of illness into the household was extensive, with 63% of household members affected by symptoms during clusters. Simultaneous and secondary transmission of gastroenteritis appeared equally common. In only 20% of clusters did more than one member submit a faecal specimen. Of clusters where two or more specimens were submitted, concordance in laboratory confirmation of pathogens was 18.8%. Our results show that clustering of gastrointestinal symptoms within households occurs commonly, but reliance on pathogen notification data will substantially underestimate the true frequency of gastroenteritis clusters.
authors.affiliation: School of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia. karin.leder@med.monash.edu.au
authors.forename: K
authors.initials: K
authors.lastname: Leder
authors.forename: M
authors.initials: M
authors.lastname: Sinclair
authors.forename: A
authors.initials: A
authors.lastname: Forbes
authors.forename: D
authors.initials: D
authors.lastname: Wain
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D004196:Disease Outbreaks; D005191:Family Characteristics; D005243:Feces / Q000382:microbiology; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology*; D006801:Humans; D008297:Male; D016017:Odds Ratio