Health Officials Investigate Growing Parasite Outbreak Across the US

Federal health officials are working to find the cause of a large outbreak of a parasite known as Cyclospora. This parasite causes a condition called cyclosporiasis, which leads to watery, explosive diarrhea, stomach cramps, and nausea. According to the Centers for Disease Control and Prevention (CDC), the number of infections is much higher than what is typically seen during the summer season, which usually lasts from May to August.

As of mid-July, the CDC has identified 1,645 lab-confirmed cases across 34 states. However, officials warn that the true number of sick people is likely much higher because many individuals with mild symptoms do not seek medical help. There is also a large backlog of over 5,000 cases that still require more analysis and interviews. The current situation is described by the CDC as a very big shift from previous years, with confirmed cases already five times higher than they were at this same time last year.

Michigan has been hit particularly hard by this outbreak. According to the Michigan Department of Health and Human Services (MDHHS), the state has reported 3,309 cases, a massive increase compared to the roughly 50 cases typically seen in the state. Officials in Michigan have noted that interviews with over 1,000 sickened people point to leafy greens as the likely source of the illness. While no official nationwide recall has been announced, some local restaurants, including Taco Bell locations in the Detroit area, have reportedly stopped serving items like lettuce, cilantro, and onions.

Donald Prater, the acting deputy commissioner for food at the Food and Drug Administration (FDA), stated that the agency is aware of a signal pointing to lettuce as a possible source. He noted that investigators are looking at multiple clusters and subclusters of the illness. Because the parasite has a long incubation period—meaning it can take days or even weeks for symptoms to appear after eating contaminated food—it is very difficult for patients to remember exactly what they ate. This makes the investigation a slow and challenging process for health officials.

This year’s outbreak has also sparked a debate about government resources. Experts in foodborne illness have criticized the current administration for cutting $11.4 billion from state and local health departments. Additionally, last year, the CDC removed Cyclospora from a list of pathogens that states were required to report to a surveillance network called FoodNet. While officials like Gwen Biggerstaff from the CDC maintain that they are still receiving data through other systems, critics argue that these changes have made it harder to track and respond to such outbreaks effectively.

For now, the CDC and FDA are urging the public to be careful. Because the parasite is often transmitted through food or water contaminated with feces, washing fresh produce thoroughly is essential. In some cases, cooking food is the best way to ensure safety. The CDC has also issued a health advisory to doctors, asking them to consider a cyclosporiasis diagnosis when patients report long-lasting or returning diarrhea. Doctors are encouraged to use specific molecular tests, as routine exams may miss the parasite.

As the investigation continues, federal officials are holding weekly meetings with states to coordinate their response. Although the CDC has not deployed extra staff to the affected areas, they are working to follow all leads provided by state health departments. With the outbreak expected to last through the end of August, health agencies are promising to provide regular updates to the public every Wednesday. In the meantime, officials emphasize that anyone experiencing symptoms should speak with a doctor to ensure they are tested and counted in the official data.