The Massachusetts Department of Public Health said it’s seeing an uptick in the number of cyclospora cases — more than anytime in the past six years — but stopped short of calling it an outbreak.
The latest DPH data on Wednesday coincided with a surge of cases linked to a large national outbreak reported by the Centers for Disease Control and Prevention. The national outbreak has spread to six states, including New Hampshire, according to the CDC.
Dr. Catherine Brown, epidemiologist with the state DPH, said in the broader context of the outbreaks in other states, the data in Massachusetts indicates an increase in the number of seasonal cases of the foodborne illness that’s higher than usual, but not yet as high as what was reported in 2019.
“I’m never in favor of panicking, I don’t think it’s helpful,” she said, “I think what’s happening this year in the United States with cyclospora is really interesting. I certainly want people to be aware of the fact that we are seeing this broad increase across the United States,” she said.
The DPH data shows the number of new cyclospora cases in the state have grown from nine in May to 32 in June to 104 in July.
That brings the total number of cases this year to 147. In 2019, state officials reported an outbreak of 211 cases in the state.
The DPH said seasonal increases in cyclospora cases are common at this time of year.
While this year’s cases are higher, the number of cases remain within the state’s historical range. Between 2016 and 2025, the annual number of cases ranged from 23 to 211.
Last month the Food and Drug Administration linked the most recent outbreak of cyclospora to iceberg lettuce supplied by Taylor Farms and grown in central Mexico.
Brown said the cases this year in the state are not geographically isolated, but we still could see a further jump in reported cases.
“I will go so far as to say I wouldn’t be surprised if we eventually exceed our most, the last 10-year peak, which was in 2019, but we are not seeing thousands of cases at this point the way many parts of the Midwest are,” she said.
Cyclosporiasis is a microscopic intestinal parasite that is spread by eating contaminated raw produce or water. It does not spread directly from person to person. It can be treated with antibiotics. Those most at risk are people with weakened immune systems.
Brown said cyclospora is more challenging than other food-borne illnesses to detect and prevent because it is a “sticky parasite,” and hard to wash off. She recommends strict food handling precautions.
“You want to make sure you’re washing everything with soap and water if you are preparing anything that’s fresh produce or fresh fruit. Anything that you can peel — that improves safety,” Brown said. If cook the food to 158 degrees that would kill the organism.
Peak cyclospora season in the U.S. is May 1 to the end of August. Brown said some data sources suggest that we may already be past the peak.
“We can’t identify the exposure for every single one of our cases, right? But the ones we can, those exposures happened a month ago, and so, history suggests that we’re on the downward side of this,” she said.
The next state case count update will be the monthly update in the first week of September.
