More than 3,000 cases of a long-lasting diarrheal illness caused by the parasite Cyclospora have been reported in Michigan and Ohio, while health departments in 31 states have identified cases that may or may not be linked to the same growing outbreak.
CNN health reporter Jacqueline Howard said Michigan has recorded more than 2,600 cases, including 44 hospitalizations, making it the hardest-hit state. Dozens of additional patients have been hospitalized across the country, although health officials are still trying to determine how many cases belong to one outbreak and where the contamination began.
Cyclospora infections can cause weeks of watery diarrhea, stomach cramps, bloating, nausea, fatigue, and loss of appetite. For some patients, the most immediate danger is dehydration severe enough to require hospital treatment.
Investigators Still Do Not Know the Source
Howard explained that the known outbreak currently includes cases in Michigan and some in Ohio, while reports from the other states remain under investigation.
The search for a source is complicated by the parasite’s long incubation period. Symptoms may not appear until two days to two weeks after exposure, making it difficult for patients to remember everything they ate or drank during the period when infection may have occurred.
Health officials are examining possible connections to contaminated fresh produce and water, including exposure at water parks or other recreational water sites.
That uncertainty is one of the most frustrating parts of the situation. People are being told to take precautions around broad categories of food, but investigators have not identified one vegetable, fruit, supplier, or location that explains all the illnesses.
Howard said symptoms may include watery or “explosive” diarrhea, along with cramping, bloating, nausea, tiredness, and reduced appetite.
The illness caused by Cyclospora is known as cyclosporiasis.
Fresh Produce Has Been Linked to Past Outbreaks
During a separate CNN discussion with Wolf Blitzer, former Centers for Disease Control and Prevention Director Dr. Robert Redfield said Cyclospora has previously been associated with several types of fresh produce.
He listed cilantro, basil, snow peas, raspberries, and lettuce among foods connected to earlier outbreaks.
Redfield explained that the parasite’s reservoir is human feces, meaning contamination can enter food or water through poor sanitation somewhere in the production, handling, or water system.
The parasite is not something that naturally grows inside a lettuce leaf or raspberry. The concern is that food or water becomes contaminated before reaching the consumer.
Redfield called Cyclospora a “sticky little parasite,” warning that ordinary rinsing may not always remove it completely from produce.
He said heating food to about 158 degrees can kill the parasite, making cooked vegetables and fruits safer from this particular threat than raw produce.
Still, telling people to simply stop eating fresh produce is not a practical long-term answer, especially when health experts normally encourage fruits and vegetables as part of a balanced diet. The more useful message is that washing can lower risk but cannot promise complete protection.
Symptoms Can Last for Weeks
Redfield told Blitzer that the illness can be extremely uncomfortable and may continue for weeks, with some cases lasting as long as a month.
People with weakened immune systems, including some patients with HIV, may experience longer and more severe illness.
Although no deaths had been reported in the figures discussed by CNN, Redfield said the outbreak had led to roughly 86 hospitalizations at the time of his comments.
Anyone experiencing continued diarrhea, abdominal pain, bloating, or other concerning symptoms should consider contacting a medical professional, especially if dehydration begins to develop.
Warning signs of dehydration can become serious because repeated diarrhea causes the body to lose both fluids and important salts. Children, older adults, and people with existing health problems may become vulnerable more quickly.
Redfield said the antibiotic commonly known as Bactrim or Septra can help treat the infection in patients who are not allergic to sulfa drugs.
He added that there are few proven alternative treatments, making proper diagnosis important rather than assuming the illness is an ordinary stomach bug that will quickly pass.
Washing Helps, but It Is Not Foolproof
Howard told CNN that people should thoroughly clean fruits and vegetables rather than giving them only a brief rinse under running water.
She suggested physically rubbing or scrubbing produce during washing and discussed using a diluted vinegar rinse made from one part vinegar and three parts water.
Later in the report, Dr. Jayne Morgan, vice president of medical affairs at Hello Heart, stressed that washing produce can reduce contamination but may not remove every Cyclospora parasite.
Morgan advised peeling fruits and vegetables when possible and removing the outside layers of foods such as lettuce.
“Washing certainly helps,” she told CNN host Victor Blackwell, but she warned that it is not foolproof.
That distinction matters because people can follow good food hygiene and still become ill. Precautions reduce risk; they do not create an invisible shield around every salad, berry, or raw vegetable.
Morgan said the parasite may also be found in contaminated water sources, including pools, splash pads, and water parks. She explained that it spreads through the fecal-oral route, in which waste contamination eventually reaches water or food.
She also noted that Cyclospora is resistant to bleach, which makes controlling it in some water environments more difficult.
The Illness Is Not Usually Spread Directly Between People
Blackwell asked Morgan what makes this outbreak different from other foodborne illnesses.
Morgan said Cyclospora is not generally passed directly from one person to another. Instead, infection is more likely to occur when someone consumes contaminated food or water.
The parasite produces microscopic forms often described as oocysts, which enter the body and develop in the intestines, leading to diarrhea and other digestive symptoms.
The lack of direct person-to-person spread may sound reassuring, but it does not make tracing the outbreak easy. A contaminated ingredient can be shipped widely, mixed into prepared foods, or eaten days before symptoms begin.
By the time several people become sick, packaging may have been discarded and meals may be difficult to remember.
That delay gives investigators a challenging puzzle with pieces scattered across grocery stores, restaurants, farms, distribution systems, and several states.
Reduced Surveillance Raises Concern
Blitzer also asked Redfield about changes to federal monitoring of foodborne diseases.
CNN reported that the CDC had scaled back part of a long-running federal and state partnership that tracked foodborne illnesses through the Foodborne Diseases Active Surveillance Network, known as FoodNet.
Redfield said reducing surveillance makes outbreaks harder to identify early.
“Surveillance is sort of the key to early identification,” he told Blitzer.
He argued that strong cooperation between the CDC, the Food and Drug Administration, and state health authorities allows public health officials to detect pathogens more quickly and begin tracing their origin.
With Cyclospora, that work is already difficult because of the delay between infection and symptoms. Less reporting can make it even harder to recognize clusters before they grow.
The problem is clear in the current investigation: cases have been reported in 31 states, but officials still do not know whether all of them are connected or which food may be responsible.
What People Can Do Now
The CNN experts offered several practical steps while investigators continue searching for the source.
People can wash produce carefully, rub firm fruits and vegetables under clean water, remove damaged areas, peel items when practical, and discard the outer leaves of lettuce and similar foods.
Cooking produce provides greater protection against Cyclospora than eating it raw, according to Redfield, although consumers do not necessarily need to abandon all uncooked fruits and vegetables.
People should also pay attention to symptoms that continue longer than a typical brief stomach illness, particularly repeated watery diarrhea, stomach cramps, bloating, exhaustion, and signs of dehydration.
Seeking medical advice can be important because cyclosporiasis can be treated, but it may not disappear quickly without the correct medication.
For now, the outbreak remains defined as much by what officials do not know as by what they do. Thousands of illnesses have been recorded, Michigan and Ohio have been hit especially hard, and cases have appeared across most of the country, yet no single source has been publicly identified.
Until investigators narrow that search, careful food handling, attention to symptoms, and early medical care remain the most useful protections available.
Raised in a small Arizona town, Kevin grew up surrounded by rugged desert landscapes and a family of hunters. His background in competitive shooting and firearms training has made him an authority on self-defense and gun safety. A certified firearms instructor, Kevin teaches others how to properly handle and maintain their weapons, whether for hunting, home defense, or survival situations. His writing focuses on responsible gun ownership, marksmanship, and the role of firearms in personal preparedness.
