CDC and FDA Expand Parasitic Outbreak Investigation to 15 U.S. States

The U.S. Food and Drug Administration and the Centers for Disease Control and Prevention widened a major foodborne illness investigation on Wednesday, August 5, 2026. Federal health officials expanded the surveillance zone to 15 U.S. states following a sharp rise in parasitic infections tied to contaminated iceberg lettuce. The nationwide outbreak involves cyclosporiasis, an intestinal illness caused by the microscopic Cyclospora parasite. Symptoms of infection include watery diarrhea, severe stomach cramps, nausea, fatigue, and muscle aches. The CDC has confirmed 10,468 laboratory-tested domestic cases and noted over 12,255 additional suspected cases across the country. The surge represents one of the largest recorded foodborne parasite outbreaks in recent United States history. State health authorities in Michigan reported 12,218 total cases on Wednesday, reflecting a single-day increase of 710 cases. Michigan officials also confirmed the first two deaths associated with the outbreak, noting that both individuals had significant underlying health conditions and contracted the illness prior to mid-July regulatory warnings. Health department records in Michigan documented 193 hospitalizations tied to the parasitic infection. Federal investigators previously traced primary clusters to iceberg lettuce distributed to Yum Brands fast-food chain Taco Bell. The contaminated produce originated from agricultural facilities operated by Taylor Farms in central Mexico. Following initial trace-back findings, the FDA issued a voluntary recall notice for specific shipments of harvested iceberg lettuce on July 17. The expansion of the federal investigation added six additional states, including Missouri, which has logged 1,095 cases. Health agencies in Arkansas, Iowa, and Nebraska also reported rising case numbers linked to commercial lettuce supply lines. CDC and FDA personnel confirmed that investigators are evaluating secondary distributors, processing centers, and retail markets to identify further contaminated produce lines entering commercial grocery networks. Public health departments across all 15 affected states advised consumers to wash fresh produce thoroughly and follow local health advisories regarding restaurant dining and raw vegetable consumption. Federal agencies confirmed that joint epidemiological investigations remain active as state laboratories process incoming clinical samples.