The U.S. Centers for Disease Control and Prevention has confirmed a multistate outbreak of cyclosporiasis. File Photo by Erik S. Lesser/EPA
July 15 (UPI) — The U.S. Centers for Disease Control and Prevention has confirmed the multistate outbreak of cyclosporiasis, the parasite-based illness, in at least four states.
The four states are Michigan, which has seen the highest rate of illness; Ohio; Kentucky; and West Virginia. But cases have been identified in 34 states, the CDC said.
The CDC had said that there was “no evidence of a single, multistate” outbreak, The Hill reported, but on Tuesday said that the hundreds of cases in the region appeared to link to a common source. The source hasn’t been confirmed, said Dr. Gwen Biggerstaff, deputy director of the CDC’s Foodbourne, Waterbourne and Environmental Diseases division. Biggerstaff hosted a call with reporters on Tuesday.
Michigan health officials have reported more than 3,700 cases of the illness and believe lettuce or salad greens could be the culprit. Dr. Donald Prater, FDA acting deputy commissioner for food, said the agency is continuing to investigate “multiple produce items, including lettuce.”
As of Wednesday, the CDC has gotten reports of at least 1,645 lab-confirmed cases of domestically acquired cyclospora since May 1, which is the start of the typical cyclosporiasis season. Biggerstaff said the agency is aware of more than 5,100 additional reports that require further analysis.
Cyclosporiasis is an intestinal illness caused by a microscopic parasite called cyclospora. It’s spread when people consume food or water contaminated with the parasite, typically fresh produce that has not been adequately washed or cooked, Biggerstaff said.
Symptoms include watery diarrhea — sometimes frequent — along with cramping, nausea, loss of appetite, fatigue and low-grade fever. Symptoms generally begin about one to two weeks after exposure, she said.
“I want to underscore an important point: This illness does not spread directly from person to person. The source of this outbreak is what we eat or drink — not casual contact with someone who’s sick,” Biggerstaff said on the call.
Biggerstaff emphasized that “the true number of infections is almost certainly higher than what’s reflected in these numbers, because many people with mild illness recover without seeking medical care and are never tested.”
Cyclospora can only be diagnosed by stool sample, the CDC said. The agency urged medical professionals to “specifically request cyclospora laboratory testing on stool specimens” to be sure of the diagnosis.
In the past, cyclosporiasis was associated with travel abroad, but in the past few years has been tied to domestic and imported produce.
The CDC said the reason cyclosporiasis investigations take longer is because people show symptoms up to two weeks after exposure to the parasite. Also, there is no whole genome sequencing of the parasite, which makes it more difficult to match the food product to the people made sick by it.
Instead, labs use genotyping, which is not as fast or precise, Biggerstaff said. In some cases, the source may never be identified.