Cyclospora infections linked to contaminated produce have spread across 34 US states, according to the CDC.
| Photo Credit:
Dado Ruvic
The U.S. Centers for Disease Control and
Prevention said on Tuesday it had confirmed 1,645 cases of an
intestinal infection from the cyclospora parasite that causes
diarrhea, nausea and other gastrointestinal symptoms and it was
investigating 5,100 possible cases in 34 states.
Michigan, the hardest-hit state, reported 3,309 cases.
WHAT IS IT?
Cyclosporiasis is an intestinal infection that can be
contracted by consuming food — typically raw fruits and
vegetables — or water contaminated with feces that transmit the
cyclospora parasite, according to the CDC.
Symptoms can range from mild to severe, with children, older
adults and people with weakened immune systems facing a higher
risk of serious illness.
While cyclosporiasis is rarely life-threatening, untreated
infections can persist for weeks and may lead to
hospitalization, particularly because of dehydration.
The U.S. has had previous outbreaks of the disease.
Michigan, for instance, said it typically records 40 to 50 cases
annually.
WHAT IS THE SOURCE?
The Food and Drug Administration is conducting traceback
investigations on multiple produce items to try to determine the
source of the outbreak.
That includes the lettuce that Michigan health officials
identified as a potential source of the outbreak. Michigan said
no specific type of produce, grower or supplier has been linked
to the outbreak.
In traceback investigations, the agency collects information
from sick people on the foods they ate in the weeks before they
became ill and works back along the supply chain, potentially
going back to the farm where an ingredient was grown.
WHAT CAN PEOPLE DO TO PROTECT THEMSELVES?
The parasite lives in contaminated food or water and is not
commonly transmitted directly from person to person.
The CDC advised people to wash their hands with soap and
water before and after preparing raw fruit and vegetables, to
wash the produce thoroughly and to scrub firm fruits and
vegetables with a clean brush.
Past outbreaks were linked to bagged salad mixes and kits,
fresh cilantro and basil, raspberries, snow peas and green
onions, Michigan has said.
For people who have cyclosporiasis, the CDC recommends
treatment with trimethoprim-sulfamethoxazole, an antibiotic
commonly sold as Bactrim, taken twice daily for seven to 10
days. People living with HIV may require longer treatment,
according to the agency.
WHERE IS THE OUTBREAK?
The CDC said that sick people began reporting symptoms in
four main states on or after June 22: Michigan, Ohio, West
Virginia and Kentucky. It also said there were numerous other
single-state investigations underway.
New York, Illinois, Kentucky, New Jersey, North Carolina and
Texas have all reported 31 cases or more as of July 13,
according to the CDC.
Case counts lag in part because of reporting delays and are
expected to rise as the CDC receives more data. Delays between
exposure and case confirmation potentially take up to six weeks,
with illness onset anywhere from two days to two weeks or more
after infection.
Cases typically rise from May 1 through August 31, the CDC
said.
WHAT SURVEILLANCE IS BEING DONE?
Cyclospora is a nationally notifiable pathogen and most
states collect robust data and share that routinely with the CDC
in its disease surveillance system, said Gwen Biggerstaff,
deputy director of the CDC’s Division of Foodborne, Waterborne
and Environmental Diseases.
Healthcare providers are legally required to report cases of
cyclosporiasis to public health departments in 47 states.
The Foodborne Diseases Active Surveillance Network, or
FoodNet, is a collaboration among the CDC, the U.S. Department
of Agriculture, the FDA and 10 state health departments. Last
July, it stopped tracking six of eight pathogens, including
cyclospora, due to funding cuts.
The goal of FoodNet is to look at trends over time and the
network does not replace national surveillance, Biggerstaff
said. Participating states continue to report cyclospora on a
national basis and the data is the same for this outbreak as
with previous ones, she said.
Published on July 15, 2026
