title: Enteric pathogens in stool samples of Chicago-area water recreators with new-onset gastrointestinal symptoms.
abstract: BACKGROUND
  Characterizing pathogens responsible for recreational waterborne gastrointestinal illness is important in estimating risk and developing management strategies to prevent infection. Although water recreation is associated with sporadic cases of gastrointestinal illness, pathogens responsible for such illness are not well characterized.
  
  
  METHODS
  A prospective cohort study was conducted enrolling non-water recreators (such as cyclists and joggers) and two groups of limited-contact waters recreators (such as boaters and kayakers): those on an effluent-dominated urban waterway and those on general use waters. Stool samples were collected from participants who developed gastrointestinal symptoms during a three-week follow-up period. Samples were analyzed for bacterial, viral, and protozoan pathogens. Logistic regression models were used to identify associations between water recreation and the presence of pathogens in stool samples.
  
  
  RESULTS
  Among 10,998 participants without gastrointestinal symptoms at baseline, 2,429 (22.1%) developed at least one symptom during 21 days of follow-up. Of those, 740 (30.5%) provided at least one stool sample, of which 76 (10.3%) were positive for a pathogen. Rotavirus, found primarily among adults, accounted for 53 of the 76 (70%) infections. Among participants with symptoms, pathogen presence was not associated with water recreation or the extent of water exposure. The range of pathogens that could be identified and sample size limitations may have contributed to this lack of association.
  
  
  CONCLUSIONS
  We did not find specific pathogens or groups of pathogens associated with recreational waterborne gastrointestinal illness. Although pathogens responsible for outbreaks of waterborne gastrointestinal illness have been described, microbes that cause sporadic cases remain poorly defined.
authors: Division of Environmental and Occupational Health Sciences, University of Illinois at Chicago School of Public Health, 2121 W. Taylor Street, M/C 922, Chicago, IL 60612, USA. sdorevit@uic.edu
authors: Samuel
authors: S
authors: Dorevitch
authors: Mark S
authors: MS
authors: Dworkin
authors: Stephanie A
authors: SA
authors: Deflorio
authors: William M
authors: WM
authors: Janda
authors: Jacqueline
authors: J
authors: Wuellner
authors: Ronald C
authors: RC
authors: Hershow
mesh_terms: D000328:Adult; D002641:Chicago / Q000453:epidemiology; D015331:Cohort Studies; D005243:Feces / Q000382:microbiology*; D005767:Gastrointestinal Diseases / Q000453:epidemiology* / Q000382:microbiology* / Q000517:prevention & control; D006801:Humans; D016015:Logistic Models; D011446:Prospective Studies; D011998:Recreation; D062065:Wastewater; D018508:Water Purification / Q000592:standards*
chemical_list: D062065:Wastewater