There’s an outbreak of a parasite that causes diarrhea in the U.S., so you may be wondering if your favorite summer salad is safe.

According to the Centers for Disease Control and Prevention, cyclosporiasis, an intestinal disease caused by a microscopic parasite called cyclospora, has been reported in 31 states since May 1. There were 843 confirmed cases and 86 hospitalizations as of July 9, with another 1,500 cases under investigation.

People get cyclosporiasis by ingesting food or water contaminated with human feces, usually during growing, harvesting, and processing. The origin of the current outbreak in the US is unknown, but in the past it has been linked to raspberries, basil, cilantro, peas, green onions and mesclum lettuce.

There have been no product recalls as officials investigate the outbreak. Local media reported that some Taco Bell restaurants had stopped serving certain items to prevent the virus from spreading.

After hours, Business Insider asked Taco Bell, McDonald’s, KFC, Starbucks, Chick-fil-A, Wendy’s, Chipotle, Burger King, Subway and the National Restaurant Association whether any procedures had changed in light of the outbreak. We did not receive a response immediately.

How to prevent cyclosporiasis

Health officials and food safety experts have advised people to consider avoiding eating foods that have previously been linked to the illness while the outbreak is investigated. These foods include lettuce, raspberries, green onions, and herbs.

In general, it is advisable to wash, rinse and scrub products thoroughly, removing outer leaves when possible. However, evidence suggests that rinsing or washing fresh fruits and vegetables is not enough to completely eliminate cyclospora, as it is sticky and tough.

Also try to cook your produce instead of eating it raw, as cyclospora cannot survive in foods with an internal temperature of at least 158 ​​degrees Fahrenheit.

It’s also important to follow standard food safety rules, such as washing your hands with soap and water before and after handling fresh produce and regularly cleaning cutting boards and utensils.

Explosive diarrhea is one of several symptoms of cyclosporiasis.

Cyclosporiasis usually causes watery diarrhea with frequent and sometimes explosive bowel movements. Other symptoms may include loss of appetite, weight loss, stomach cramps, bloating, gas, nausea, fatigue, vomiting, body aches, headaches, low-grade fever, and other flu-like symptoms.

The actual number of infections is likely much higher, since most people can recover from the illness at home, and those who visit a doctor may not get tested for cyclosporiasis because it is expensive and involves taking multiple stool samples over several days, Katelyn Jetelina, an associate professor of epidemiology at the Yale School of Public Health, wrote in her public health newsletter, Your Local Epidemiologist, on July 11.

Not all people infected with cyclospora experience symptoms, and they usually only begin to appear about a week after exposure to cyclospora, making infections difficult to track. Severe cases can be treated with antibiotics.