title: Outbreaks of short-incubation ocular and respiratory illness following exposure to indoor swimming pools.
abstract: OBJECTIVE
  Chlorination destroys pathogens in swimming pool water, but by-products of chlorination can cause human illness. We investigated outbreaks of ocular and respiratory symptoms associated with chlorinated indoor swimming pools at two hotels.
  
  
  METHODS
  We interviewed registered guests and companions who stayed at hotels X and Y within 2 days of outbreak onset. We performed bivariate and stratified analyses, calculated relative risks (RR), and conducted environmental investigations of indoor pool areas.
  
  
  RESULTS
  Of 77 guests at hotel X, 47 (61%) completed questionnaires. Among persons exposed to the indoor pool area, 22 (71%) of 31 developed ocular symptoms [RR = 24; 95% confidence interval (CI), 1.5-370], and 14 (45%) developed respiratory symptoms (RR = 6.8; 95% CI, 1.0-47) with a median duration of 10 hr (0.25-24 hr). We interviewed 30 (39%) of 77 registered persons and 59 unregistered companions at hotel Y. Among persons exposed to the indoor pool area, 41 (59%) of 69 developed ocular symptoms (RR = 24; 95% CI, 1.5-370), and 28 (41%) developed respiratory symptoms (RR = 17; 95% CI, 1.1-260) with a median duration of 2.5 hr (2 min-14 days). Four persons sought medical care. During the outbreak, the hotel X's ventilation system malfunctioned. Appropriate water and air samples were not available for laboratory analysis. CONCLUSIONS AND RELEVANCE TO PROFESSIONAL PRACTICE: Indoor pool areas were associated with illness in these outbreaks. A large proportion of bathers were affected; symptoms were consistent with chloramine exposure and were sometimes severe. Improved staff training, pool maintenance, and pool area ventilation could prevent future outbreaks.
authors: Enteric Diseases Epidemiology Branch, National Center for Zoonotic, Vector-borne and Enteric Disease, Centers for Disease Control and Prevention, Atlanta, GA 30333 USA. abowen@cdc.gov
authors: Anna B
authors: AB
authors: Bowen
authors: James C
authors: JC
authors: Kile
authors: Charles
authors: C
authors: Otto
authors: Neely
authors: N
authors: Kazerouni
authors: Connie
authors: C
authors: Austin
authors: Benjamin C
authors: BC
authors: Blount
authors: Hong-Nei
authors: HN
authors: Wong
authors: Michael J
authors: MJ
authors: Beach
authors: Alicia M
authors: AM
authors: Fry
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002700:Chloramines / Q000032:analysis / Q000633:toxicity*; D015331:Cohort Studies; D004196:Disease Outbreaks / Q000517:prevention & control; D004781:Environmental Exposure / Q000517:prevention & control; D005128:Eye Diseases / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012120:Respiration Disorders / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D012307:Risk Factors; D013551:Swimming Pools; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity
chemical_list: D002700:Chloramines; D014874:Water Pollutants, Chemical