Cases of the diarrhea-causing parasitic infection cyclosporiasis, linked to iceberg lettuce, have expanded to six additional states, according to the Centers for Disease Control and Prevention.
An unprecedented wave of infections has hit the United States since May, resulting in two deaths. The CDC, which lags significantly behind states in reporting infections, pinpointed 10,468 laboratory-confirmed cases across 47 states between May 1 and its latest update Aug. 4. Thousands more have not yet been confirmed by laboratories.
Ohio and Michigan have led the charge in reporting cyclosporiasis incidents, with Michigan's health department stating on Aug. 4 that it had 11,508 cases, including the first two deaths identified in the nationwide outbreak.
The Ohio Department of Health's infectious disease dashboard showed 4,087 confirmed cases of cyclosporiasis between May 1 and its last update on July 28.
Not all of these clusters have been linked to the same source, however. The largest outbreak, centered in Michigan, has been traced by the Food and Drug Administration back to recalled iceberg lettuce grown by produce giant Taylor Farms in central Mexico. On July 24, the Taylor Farms-related outbreak was identified as reaching nine states: Illinois, Indiana, Kansas, Kentucky, Michigan, Ohio, Oklahoma, Pennsylvania and West Virginia.
It has since expanded to include Missouri, Arkansas, Iowa, Nebraska, New Hampshire and North Carolina, according to reports citing sources familiar with the matter from Reuters, the Washington Post and the New York Times. The CDC declined USA TODAY's requests to confirm this information and said Aug. 4 that it planned to update the numbers and states on its public page about the outbreak.
The CDC page still showed the count of nine states from July as of Wednesday, Aug. 5.
Cyclosporiasis, an illness caused by the parasite Cyclospora cayetanensis, results in unpleasant gastrointestinal symptoms, often associated with food poisoning, such as diarrhea, nausea and vomiting. It is usually contracted through contaminated food or water, and it is not generally known to be deadly; however, it can cause more serious complications in people with compromised immune systems or other underlying health issues.
Many cases go unreported, as it can take a long time after exposure to become sick and people recover at home without visiting a doctor.
Multiple cyclosporiasis outbreaks under investigation
In addition to the Michigan-centered outbreak, officials are investigating multiple separate clusters of the gastrointestinal illness, including one that has sickened at least 93 people. The FDA has not yet identified the source of additional outbreaks.
The source of a cyclosporiasis cluster is more difficult to track than foodborne illnesses due to a long incubation period, difficulty obtaining samples and the inability to use the same genetic tracking tools available for pathogens like E. coli and listeria, as previously reported by USA TODAY.
While Taylor Farms has pointed to FDA sampling that was not positive for cyclospora, the agency made clear that a positive or negative test on a food sample does not change the results of its traceback investigation, as reported by USA TODAY.
Last year, the CDC scaled back a decades-long federal-state partnership that monitors foodborne illnesses, including those caused by cyclospora.
Health and Human Services Secretary Robert F. Kennedy Jr. said during a July 21 news briefing that the outbreak was "under control"; however, critics have pointed to cuts to relevant health agencies, with some saying that scaled-back surveillance and limited staffing enabled not only the cyclospora spread, but other recent outbreaks like screwworm.
This article originally appeared on USA TODAY: Cyclospora outbreak tied to lettuce expands to 15 states as cases rise
