Test results Monday confirmed that a fourth Bellingham girl who attended a recent high school cheerleader dance camp at Eastern Washington University suffered E. coli O157 food poisoning, a Whatcom County health official said.
Only one Bellingham girl was hospitalized. Epidemiologists are sending surveys to the nearly 130 people who attended the camp to find the source of the bacteria. Contaminated food or water containers are suspected, but the investigation is open, state health officials said.
"Until those (surveys) come in, it's going to be difficult to determine anything," said Paul Chudek, environmental health supervisor for the Whatcom County Department of Health. "You've got a group of individuals spending a tremendous amount of time together doing the same thing. It's difficult to sort out."
Laboratory tests have confirmed 31 cases of the food-borne illness, and results are pending in more than a dozen other cases, said Dr. Kim Thorburn, director of Spokane Regional Health District.
Officials widened the investigation after tests confirmed the presence of E. coli bacteria in four individuals who did not attend the camp, including one who ate a meal at EWU's Tawanka Commons dining hall, where the cheerleaders ate.
E. coli bacteria normally live in the intestines of humans and animals and most strains are harmless. But E. coli O157 produces toxins that lead to severe stomach cramps and diarrhea, and in rare cases, kidney damage and even death.
Fourteen Bellingham girls attended the camp July 11-14 in Cheney. About half of camp attendees were Spokane County girls heading into 10th through 12th grades. The others came from Whatcom and Grant counties and four western Montana towns.
Meat, a common source of E. coli contamination, was not on the menu during the camp, EWU officials said. The investigation was trying to determine if food was brought to the camp from off campus, health officials said.
Washington averages 150 to 250 cases of E. coli O157 cases each year.