For Release: June 10, 2009
Contact: Pamela Williams
Office of Communications
OSDH Announces Results of Triathlon Illness Investigation
The Oklahoma State Department of Health (OSDH) announced today that an investigation of gastrointestinal illness reported in a recent Oklahoma City triathlon was related to exposure to water during swimming practice sessions or during the swim portion of the event.
The OSDH began its investigation after receiving reports that some participants became ill following their participation in the Boathouse International Triathlon held in Oklahoma City May 16-17. State health epidemiologists queried participants through an online survey to try to determine what event or personal exposures could have led to diarrhea, vomiting and other gastrointestinal symptoms. Of the 367 participants, 218 responded to the survey and of that number, 45 met the OSDH case definition for illness, which was an acute onset of diarrhea in a 24-hour period and/or vomiting following the event. Health officials also sought stool specimens from those reporting illness.
The OSDH was able to determine that those athletes that consumed more than approximately an ounce of river water were significantly more likely to develop illness. “The amount of time spent swimming in the river during the practice sessions and during the event is the only significant exposure associated with the development of diarrheal illness among participants,” said Lauri Smithee, chief of the OSDH Acute Disease Service.
Health officials investigated several other potential sources of illness including consumption of foods and drinks provided for athletes during the event and at the expo center, consumption of foods and drinks at an event reception, and dining at area food service establishments while staying in Oklahoma. Analysis of the survey data indicated that the risk of developing a diarrheal illness increased as the amount of time swimming in the river increased. No single agent responsible for the outbreak was found. Laboratory analyses of stool specimens from a few ill athletes were positive for different gastrointestinal agents, including norovirus, and a couple of different kinds of bacteria and parasites, all of which are compatible with this gastrointestinal outbreak and which could be associated with exposure to water contaminated with human or animal waste.
The OSDH has shared results of the investigation with triathlon event organizers and Oklahoma City officials. State health officials are coordinating with the City of Oklahoma City, the Oklahoma City-County Health Department, the Department of Environmental Quality, and the Oklahoma Water Resources Board to develop a work group following this outbreak.