Health officials are investigating the largest recorded cyclospora outbreak in the United States, with more than 11,500 confirmed and suspected cases reported across 41 states, according to the CDC. The outbreak has caused at least 308 hospitalizations and no reported deaths so far.
Federal investigators say the main multistate cluster appears to be tied to shredded iceberg lettuce sourced from central Mexico, with traceback work pointing to Taylor Farms de Mexico. A voluntary recall was issued on July 17 for iceberg lettuce products sourced from central Mexico, and the investigation later expanded beyond the original cluster as more cases surfaced in additional states.
Health Secretary Robert F. Kennedy Jr. said the outbreak was under control, even as public health officials continued to track new cases.
Outbreak scope
The CDC’s national tally includes more than one investigative thread, not just a single cluster. Officials have said the outbreak has been identified through a mix of lab-confirmed domestic cases and additional suspected illnesses, and they have cautioned that recent infections may not yet appear in the total because of reporting delays.
The nine-state multistate investigation originally at the center of the probe included Indiana, Kentucky, Ohio, West Virginia, Illinois, Kansas, Oklahoma and Pennsylvania, along with Michigan, which has recorded the overwhelming majority of cases. CDC tracking also suggests that the full national burden extends well beyond those states.
Michigan’s role
Michigan has become the outbreak’s epicenter. State health officials reported 7,171 cases by July 22, with 102 hospitalizations, and later updates showed the state continuing to account for the vast majority of reported illnesses.
The Michigan numbers have climbed much faster than the CDC’s national figures because state surveillance can move faster than federal confirmation and because some cases are still under review. That gap is common during large foodborne outbreak investigations, especially when investigators are trying to match patient interviews, laboratory testing and food traceback records.
Source under review
The strongest evidence currently points to shredded iceberg lettuce used by Taco Bell locations in several states, according to federal reporting and company actions taken during the investigation. Taco Bell removed the ingredient from its supply chain as investigators continued to trace the contamination source.
Still, officials have not ruled out other contaminated produce items. Public health reporting and expert commentary have also raised the possibility that parsley, cilantro and other fresh produce from central Mexico could be involved in separate or secondary clusters under investigation.
What Cyclospora is
Cyclospora cayetanensis is a microscopic parasite that causes an intestinal infection called cyclosporiasis. People typically become infected by eating food or drinking water contaminated with fecal material containing the parasite, and symptoms often include watery diarrhea, stomach cramps, bloating, nausea, fatigue and dehydration.
Unlike some other foodborne illnesses, cyclospora does not usually spread directly from person to person. The parasite must mature in the environment before it becomes infectious, which is one reason outbreaks are often tied to produce rather than person-to-person transmission.
Symptoms and timing
Symptoms usually begin about a week after exposure, though the incubation period can range from roughly 2 to 14 days. In some cases, the illness can linger for several weeks or even longer if not properly treated, which makes it especially disruptive for people who experience repeated diarrhea and dehydration.
That timing also helps explain why outbreak counts can keep rising after a contaminated ingredient has already been removed from sale. People may not seek care right away, and some cases are not identified until public health officials connect the dots through interviews and lab work.
Consumer advice
Public health authorities are telling consumers to discard recalled iceberg lettuce products and avoid eating any product included in the recall. They also recommend extra caution with bagged salads, raw herbs and other ready-to-eat produce items, especially during an active outbreak investigation.
Food safety experts generally say whole heads of lettuce are safer than prewashed chopped greens because the outer leaves can be removed and the produce can be washed more thoroughly. Cooking is the most reliable way to destroy cyclospora, since heat kills the parasite.
What’s still unclear
Investigators have not publicly closed the case on every illness in the national count. The exact contamination point remains under review, and Mexican authorities have said their own samples from the supplier tested negative, which adds another layer of uncertainty to the probe.
The outbreak is also still evolving, which means counts, affected states and the list of suspect foods could change again as new interviews and lab results come in. For now, officials are treating the lettuce-linked cluster as the leading theory while continuing to search for any additional sources.
