What is cyclosporiasis? Parasite outbreak causing severe diarrhea in U.S. states; symptoms and causes explained
A parasitic infection called cyclosporiasis has sparked concern in several U.S. states after health officials reported an increase in cases associated with severe gastrointestinal symptoms, including prolonged and sometimes severe diarrhea.
Michigan has reported one of the largest clusters of infections, recording hundreds of infections in recent weeks. While officials suspect contaminated fresh produce may be the cause of the outbreak, investigators have not identified a specific food, brand or supplier as responsible.
What is cyclosporiasis?
According to the Centers for Disease Control and Prevention, cyclosporiasis is a foodborne illness caused by the parasite Cyclospora.
Infection occurs when people consume food or water contaminated with the parasite, which is usually spread through contact with feces. It usually affects the intestines and can cause symptoms that last for weeks if left untreated.
Symptoms usually appear 2 to 14 days after exposure, the CDC says. The most common symptoms are “watery diarrhea with frequent and sometimes explosive bowel movements.”
Other symptoms may include stomach cramps, nausea, vomiting, fatigue, loss of appetite, weight loss, gas, body aches, and low-grade fever.
Although cyclosporiasis is usually not life-threatening, untreated infection may persist for weeks, and symptoms sometimes disappear and return.
Why are U.S. health officials investigating the outbreak?
Health officials have reported cases of cyclosporiasis in several states, including Michigan, Illinois, New York and Texas.
In Michigan, the Michigan Department of Health and Human Services (MDHHS) said cases are rising rapidly, with the number of infections reaching at least 700. Monroe County has the highest number of reported cases in the state, followed by Washtenaw, Lenawee, Shiawassee and Wayne counties.
Officials believe contaminated fresh produce is the main possible source but have not yet identified the specific product.
Dr. Natasha Bagdasarian, Michigan’s chief medical executive, said the rising number of cases is making it more difficult to trace the source.
“So we have 700 people that need to be interviewed, which makes it more complicated. But I can tell you our main hypothesis right now is that the produce is contaminated,” Baghdasarian said.
How is cyclosporiasis spread?
This parasite is commonly associated with fresh fruits and vegetables because these foods may have become contaminated during growing, harvesting, processing, or handling. Officials say determining the source can be difficult because food supply chains often involve multiple states.
“Some food is grown in one state, packaged and processed in another state, and then shipped to various states,” Baghdasarian said.
Previous cyclosporiasis outbreaks have been linked to food products including bagged salad mix, fresh herbs such as cilantro and basil, raspberries, snow peas and green onions.
How can people prevent cyclosporiasis?
Health officials recommend taking precautions when preparing fresh produce.
The CDC recommends that people wash their hands before and after handling fruits and vegetables, rinse produce thoroughly before eating, and scrub hard items like cucumbers and melons with a clean brush.
People should also refrigerate cut or cooked produce immediately. For food that can be cooked, heating it to at least 158°F (70°C) will help kill parasites.
Anyone who develops persistent diarrhoea, severe abdominal pain, dehydration or worsening symptoms should seek medical advice as cyclosporiasis may require antibiotic treatment.
