King County health officials are closely monitoring a nationwide outbreak of a parasite that causes severe diarrhea but say there is no evidence so far that Washington is part of the outbreak.
During a King County Board of Health meeting Thursday, public health leaders said there are currently 19 reported cases of Cyclospora infection in King County. Of those, only one appears to have been acquired locally, and officials do not believe it is connected to the multi-state outbreak.
However, Public Health – Seattle & King County has issued a health alert asking healthcare providers to specifically test for the parasite in patients with symptoms consistent with cyclosporiasis.
“We are very closely monitoring for any signs that people may have been exposed to the parasite locally,” said Dr. Sandra Valenciano, director and health officer for Public Health – Seattle & King County.
Health officials emphasized that King County is currently seeing its normal number of cases and that most people who became sick had recently traveled.
Meanwhile, investigators have narrowed down at least one source of the parasite. The CDC issued a warning against eating shredded iceberg lettuce from Taco Bell in five states, including Indiana, Kentucky, Michigan, Ohio and West Virginia.
According to the Associated Press, sources say the lettuce was supplied by California-based Taylor Farms, a major produce distributor that also manufactures packaged salad kits. The CDC said the lettuce originated from Mexico.
Seattle-area food safety attorney Bill Marler believes the outbreak may extend beyond Taco Bell – considering there are already more than 7,000 cases nationwide.
“I don’t think it is going to be limited to Taco Bell,” Marler said. “It may be limited to iceberg lettuce, but it’s most likely that a lot of these several thousand people are linked to the same product,” Marler said. He’s already filed one lawsuit in Ohio against Taco Bell on Thursday and has about 50 other potential clients who’ve contacted his office.
Marler said Cyclospora can cause severe gastrointestinal illness because the parasite has a hard outer shell and described it as “sticky” – which allows it to cling to the intestines.
“So that’s why you have difficulty washing it off, and chlorine frankly doesn’t really do it unless you put a lot of chlorine on it. It gets in your gut, takes a week to two to percolate there,” Marler said. Symptoms can last for weeks or even months if left untreated.
Although local public health officials are not recommending people avoid fresh produce in Washington, Marler said consumers who want to be extra cautious – like the very young and the elderly, pregnant women, and the immunocompromised - may want to avoid bagged salads until investigators more precisely identify the source of the outbreak.
Taco Bell said it has “taken immediate action to voluntarily remove potentially impacted lettuce” from affected restaurants.
Taylor Farms has not publicly commented.
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