Cases of parasitic outbreak remain low in Oregon as other states see surges 

Oregon health officials have recorded a handful of verified cases of a parasitic intestinal illness in the state over the past two months, as outbreaks involving the disease continue to grow in other parts of the country. 

Data the Oregon Health Authority released last week shows that in both May and June, public health officials recorded seven cases of cyclosporiasis in the state. The parasite cyclospora infects the small intestine, and symptoms of the illness can include watery or explosive diarrhea, loss of appetite, bloating, weight loss, stomach cramps and nausea. 

But Oregon’s current case levels remain far below the hundreds of cases confirmed by the Centers for Disease Control and Prevention, which has been tracking the outbreak in 31 states since May but lagging behind state-level data in areas where the outbreak has been most pronounced. The Trump administration has gutted funding for local public agencies and reduced state-level surveillance requirements for a federal program to monitor foodborne illness. 

The outbreak is currently concentrated in states such as Michigan, New York, Illinois and Texas, but some health officials on the West Coast have expressed concern that there could be spillover from the Midwest.

None of Oregon’s recent cases of cyclosporiasis have been connected to a common food source or broader outbreak investigation, according to Jonathan Modie, a spokesperson for the Oregon Health Authority. He noted that federal health officials are still investigating the source of the outbreak in other states.

“Many other states have also not reported an increase in cases,” Modie wrote in an email. “The reasons for this pattern remain unknown, and there is a possibility that specific risk factors (e.g., contaminated products or other common exposures) may not be present in Oregon. Until the factors driving the national situation are understood, we cannot know whether case numbers in Oregon will change in the future.”

So far, current cases are lower than previous years’ data. In June 2024 and July 2025, the Oregon Health Authority recorded 12 cases, the highest number for a single month in recent years. 

The parasite thrives on produce such as lettuce which is not cooked and can remain contaminated when washed off. Public health experts recommend that people wash their produce thoroughly, avoid pre-cut or bagged salad mixes, cook foods whenever possible and be cautious of the source of drinking water. 

Cyclosporiasis is treatable with antibiotics, but people with healthy immune systems can often recover without any additional treatment. Without treatment, the illness may last from a few days to a month or longer, according to the CDC.