title: [Health complaints in relation to quality of swimming water in participants of a triathlon].
abstract: Participants in a triathlon in Alphen aan den Rijn, the Netherlands, reported gastrointestinal symptoms to the local health authority. A study was performed to establish the number of complaints and the relation with the microbiological water quality at the surface water swimming site, which met current standards. An epidemiological survey was carried out with a questionnaire among 629 participants, with non-participating relatives as controls. Faecal samples of patients and water samples were investigated by conventional methods. 439 participants and 217 controls completed the questionnaire. 140 participants had at least one gastro-intestinal symptom and 28 (6.4%) had highly credible gastroenteritis. Participants had an odds ratio for gastro-enteritis of 14.7 (95% CI: 2.39-604.45). Electron microscopic examination in six of 12 patients showed viruses able to cause such symptoms. Water samples showed considerable faecal pollution at the time of the triathlon (geometric mean counts: thermotolerant coliforms 725/100 ml; faecal streptococci 23/100 ml). The most likely source is the effluent discharge of the nearby waste water treatment plant. A surface water swimming site meeting current standards does not exclude health complaints among tri-athletes.
authors.affiliation: Rijksinstituut voor Volksgezondheid en Milieuhygiëne, Bilthoven.
authors.forename: P
authors.initials: P
authors.lastname: Gruteke
authors.forename: G J
authors.initials: GJ
authors.lastname: Medema
authors.forename: T
authors.initials: T
authors.lastname: Coenen
authors.forename: A H
authors.initials: AH
authors.lastname: Havelaar
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004812:Epidemiologic Methods; D005260:Female; D005759:Gastroenteritis / Q000453:epidemiology* / Q000382:microbiology; D006306:Health Surveys; D006801:Humans; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D013550:Swimming; D014871:Water Microbiology
vernacular_title: Gezondheidsklachten in verband met de zwemwaterkwaliteit bij deelnemers aan een triathlon.