A nationwide outbreak of diarrhea, hitting at least 1,700 people, has reached Utah

SALT LAKE CITY — Cases of diarrhea caused by a microscopic parasite called cyclospora are climbing across several states and have reached Utah, according to data from the Centers for Disease Control and Prevention.

As of Friday morning, Utah was reported to have “one to 10” people confirmed with the parasite, according to the CDC’s website.

The epicenter of an outbreak is Michigan, where more than 1,500 people have fallen ill as of Friday. Ohio has also seen nearly 200 cases. Other states, including New York, Illinois, Indiana, North Carolina, and Texas have also reported a jump in cases, although it’s not clear whether they’re all part of the same outbreak.

Since May 1, the CDC has received reports of 843 domestic cases of cyclosporiasis. The agency said it’s aware of more than 1,500 potential cases that require further analysis to confirm the illness as domestically acquired cyclosporiasis.

The CDC says “multiple states” have reported an increase in cases in the last two weeks compared with the same period in 2025.

“CDC is aware that states are likely to report higher case counts of cyclosporiasis than reflected in CDC data and is working closely with states to update numbers as additional cases are confirmed,” it said Friday.

While it’s not likely to kill you, cyclosporiasis, by all accounts, is not something you want to deal with. The watery diarrhea, cramping and bloating it causes can quickly leave you dehydrated and even land you in the hospital. More than 70 people have been hospitalized in Michigan and Ohio.

“If you get norovirus or something, you might have a rough 24 or 48 hours, but people with this parasite can be sick for weeks or sometimes even months with a sort of relapsing pattern, and so that can really wear down your body,” said Dr. Caitlin Rivers, an epidemiologist and senior scholar at the Johns Hopkins Center for Health Security. She recently wrote about the outbreak in her “Force of Infection” newsletter.

Importantly, investigators say they haven’t yet been able to determine the source or sources causing this year’s cyclosporiasis cases.

But based on past experience with this bug, there are some ways you can try to keep yourself safe.

Know how it infects people

The good news is that cyclosporiasis doesn’t pass directly from person to person. You get it by eating or drinking something that’s been contaminated several weeks prior, usually fresh produce or water from a swimming pool.

This parasite is resistant to bleach, so it can show up in recreational water sources like chlorinated swimming pools and splash pads, but also in lakes and rivers. If you have an outbreak in your area, especially, it might be best to avoid public swimming areas.

Cook your fruits and veggies

When it comes to fresh fruits and vegetables, the safest thing to do to prevent getting sick is to cook them, Rivers said.

Cooking food to an internal temperature of 158 degrees Fahrenheit or higher kills cyclospora, according to the Michigan Department of Health and Human Services.

How long that takes will depend on your cooking method. Using a food thermometer can help you know that you’ve reached a safe temperature.

Always wash your produce

If it’s something you can’t really cook, like salad greens, you’ll want to wash it thoroughly — for at least a minute — by immersing it in water and swishing gently by hand. The bowl of a salad spinner is effective for this, for example.

Researchers have also tested a rinse of one part vinegar to three parts water, and this also works to remove most cyclospora spores from produce.

In one study, even careful washing couldn’t remove all cyclospora, however, which proved to be stickier than other parasites.

“My read of this study is that rinsing helps, but it’s not reliable,” said Rivers.

Other practices that may help reduce the risk include breaking off and discarding the outer leaves of a head of lettuce, and scrubbing firm fruits and vegetables with a soft brush while rinsing.

Consider steering clear of certain high-risk foods

You don’t have to avoid all raw fruits and vegetables because of an outbreak with an undetermined cause. But if you are particularly vulnerable, perhaps because of age or medications that lower your immune function, you could consider steering clear of foods that have been involved in outbreaks in the past.

They include foods that are harder to wash, or that people might be less diligent about washing, including:

• Raspberries
• Basil
• Salad mixes (including vegetable trays and coleslaw)
• Cilantro
• Berry/fruit mixes
• Lettuce
• Snow peas

What to do if you get sick

In the midst of a known outbreak, infectious disease experts recommend heading to the doctor for a diagnosis and treatment if you have diarrhea for longer than 48 hours.

“If it’s been more than 48 hours, it’s reasonable to test for it,” said Dr. Rebecca Schein, an infectious disease expert at Michigan State University Health Care.

Standard tests to look for stomach bugs don’t typically include cyclospora. Your doctor may need to special order it. Because the parasite sheds intermittently, you may also need several tests spaced 24 hours apart to get an accurate diagnosis.

Treatment is seven to 10 days of the combination antibiotic sulfamethoxazole-trimethoprim, which is sold as Bactrim or Septra.

“The recommendation is to treat people who have cyclosporiasis because it can last so long, and it’s just uncomfortable,” Schein said. “And it can increase, you know, spread into the environment if we don’t treat it.”

Contributing: Cassidy Wixom