Be ‘aware but not alarmed’: Nationwide cyclospora outbreak has not reached Spokane yet

Outbreak of a diarrhea-inducing parasite swept across the country in recent weeks, but so far Spokane has been spared.

Though risk of cyclospora remains low in the Pacific Northwest, some precautions are warranted, local health officials say.

“At this moment, it’s not a particularly high concern in this area. But that’s why it’s important to be aware but not alarmed,” said health officer Francisco Velázquez of the Spokane Regional Health District.

There are typically between 2,000 and 3,000 cases of cyclospora infection in a given year. In 2026, there have been more than 7,000 cases nationwide as of mid-July. Thirty-six states, including Washington, have reported cases of the parasitic disease this year, but they have mainly concentrated in four Midwestern states. Michigan alone accounts for more than 2,500 of the cases.

Washington has only identified 27 cases within its borders. Twenty-two of those infections resulted from international travel to areas where the parasite is endemic. None of those cases have been linked to the nationwide outbreak or originate in Spokane, Velázquez said.

“We have not been notified of any cases in Spokane County,” he said.

Human-to-human transmission of the parasite does not occur, Velázquez added. Illness will not spread from contact with an infected individual, so it is unlikely cases in Washington state will be connected to the nationwide outbreak unless an infected individual visited those places.

Cyclospora is a single-cell parasite that uses humans as its hosts. Once ingested, the protozoa infests the intestine and reproduces. Egg-like oocysts exit the body through waste and hope to infect another unsuspecting human host. Damage to the intestine caused by the breeding is the cause of explosive diarrhea, said Kali Kniel, professor of microbial food safety at the University of Delaware.

“You have this organism that is replicating in the intestine and causing damage. What results is watery diarrhea because nutrients can’t be absorbed into intestinal cells the way they normally do,” she said.

Other symptoms associated with infection are loss of appetite, weight loss, cramping, nausea, fever and a lot of gas. These symptoms can last from days to several weeks. Even when one initially recovers from diarrhea, symptoms can unexpectedly return after days of normal bowel movements, Kniel said.

“It is a frustrating condition because just when you feel like you’ve recovered, symptoms will return. That is because the organism is undergoing another cycle of replication in the intestine and the body hasn’t cleared it yet,” she said.

Eventually the body will expel the parasite. Symptoms are typically not life-threatening and rarely require hospitalization. Antibiotic medication can lessen and shorten recurrence of symptoms, she noted.

The cause of the outbreak is unclear. Investigators have identified shredded iceberg lettuce supplied to Taco Bell restaurants by Taylor Farms as a potential source, according to two individuals familiar with the investigation who spoke with the Washington Post. The two spoke on the condition of anonymity to share details of the ongoing investigation.

Kniel suspects the large number of cases are the result of several outbreaks occurring at the same time.

Cyclospora is one of the few parasites whose only hosts are human, which makes the virus difficult to study. Kniel hopes the outbreak will lead to more research into microscopic parasites. The CDC has seen cuts to foodborne illness research beginning last year.

Tracing is hindered by the parasite’s two-week incubation period. Cases often go undiagnosed, and it can be difficult to pinpoint the exact point of ingestion, Kniel said.

The oocysts of the organism often attach themselves to leafy greens like lettuce, cilantro and basil. The eggs are often spread from human feces to untreated water systems that are used to water the plants.

To protect against ingesting cyclospora, Velázquez recommends redoubling cleanliness in the kitchen. Wash hands with soap before and after handling produce. Wash produce with water alone before consumption and remove the outer layer of whole lettuce. Stir frying or otherwise cooking leafy greens above 165 degrees will kill the parasite.

“One recommendation is perhaps avoid prepackaged, preprepared salads and bags of vegetables for the time being. Try to get whole and fresh produce,” he said.

Kniel hopes concern over cyclospora does not stop people from enjoying healthy food.

“I don’t want people to stop eating fresh produce. If you’re buying local, usually you know local produce has fewer points of possible contact. Buy that, enjoy that. I’m eating fresh produce, so I hate to see that so many people are completely avoiding it,” she said.