Shredded iceberg lettuce supplied to Yum Brands' Taco Bell restaurants by California-based supplier Taylor Farms has been identified by investigators as a potential source of contamination in the cyclosporiasis outbreak that has sickened thousands of people in the United States, the Washington Post reported on Thursday, citing two individuals familiar with the investigation.
While the US has experienced outbreaks of the parasitic intestinal infection before, the scale and geographic spread of this year's outbreak are significantly larger, prompting concern among health officials.
The outbreak, which began on May 1, has been concentrated in Michigan, with Ohio and New York also reporting a large number of infections. Michigan health officials on Thursday reported 4,312 cases of the parasitic illness.
The US Centers for Disease Control and Prevention said this week it had identified a likely link among cases reported in Michigan, Ohio, West Virginia and Kentucky, suggesting many of the infections may stem from a common source, according to the report.
Taco Bell said earlier this week it had removed a limited number of ingredients from some restaurants as a precautionary measure, but stressed that US health authorities had not linked the outbreak to the chain, any specific food item or a supplier.
Yum Brands and Taylor Farms did not immediately respond to Reuters requests for comment.
The Department of Health and Human Services, which oversees the US Food and Drug Administration, did not immediately respond to a Reuters request for comment.
Separately, Bloomberg News reported that the US FDA is expected to soon advise consumers to avoid shredded lettuce at Taco Bell restaurants in Michigan, Ohio, West Virginia, Kentucky and Indiana.
Cyclosporiasis can be contracted by consuming food, typically raw fruits and vegetables or water contaminated with feces, and causes diarrhea, nausea and other gastrointestinal symptoms.
