A surge in cysticercosis cases nationwide has many people concerned about eating certain produce, but experts say locally grown fruits and vegetables, like those sold at farmers markets, may be a safer option.
Cyclosporiasis, caused by the microscopic parasite Cyclospora caetanensis, is usually spread through contaminated food such as produce or water, according to the Centers for Disease Control and Prevention.
As of July 13, the agency has confirmed more than 1,600 infected people nationwide, and is working to confirm more than 5,000 more.
State officials have previously tallied even higher totals. In Michigan alone, authorities were tracking more than 3,700 cases as of July 15, according to the state Department of Health and Human Services.
CDC officials said on July 14 that the cases in Michigan, Ohio, West Virginia and Kentucky are likely related. Michigan officials have not yet determined the cause of the spike in infections, but indicated they are investigating whether lettuce is the source of infections in the state.
As the disease continues to spread, here’s what you need to know about safe practices for fruits and vegetables, especially where they are purchased.
Is farmers market produce safe from the risk of cyclosporosis?
While not a complete guarantee, experts told USA TODAY that produce at farmers markets can be a safer option because it’s more likely to be sourced from local producers. But no produce is risk-free, especially since authorities have not yet identified the exact source of this outbreak.
Experts said if the disease is spreading from produce, the food could be contaminated by a contaminated water source at the cultivation site, and locally grown produce may be less likely to be affected by Cyclospora.
“It’s not where it’s sold, it’s where it’s grown,” said Amesh Adalja, a senior fellow at the Center for Health Security at the Johns Hopkins Bloomberg School of Public Health.
Dana Mordue, an associate professor of pathology, microbiology and immunology at New York Medical College, said past outbreaks of cyclosporiasis in the United States have been traced to produce from other countries, and that may be due in part to other countries using contaminated irrigation sources.
“A lot of times this comes in from overseas, and in some places the procedures may be more lenient than what you would think is done in the U.S.,” Mordue said. “But in this case, given the scale of the spread, it makes us at least wonder if something is going on within the United States.”
Joellen Russell, a professor of climate and integrated sciences at the University of Arizona, said changing weather patterns in the United States, such as increased heavy rainfall, could cause agricultural runoff and sewage flooding, contaminating irrigation water used for fresh produce.
What about a backyard garden?
Experts said people with backyard gardens are likely to be safe, again depending on the source of irrigation.
“It has to do with the water we’re using for irrigation,” Adalja said.
Adalja and Mordue said municipal water supplies in the United States are not typically contaminated with human feces, making it unlikely that the problem stems from the water source here.
“Typically, I know what kind of fertilizer I use in my garden,” Mordue added.
Does washing produce help? Yes and no
The CDC recommends washing fruits and vegetables thoroughly under running water to reduce the risk of foodborne illness. But some experts say that’s not enough when it comes to crosspolyiasis.
“Washing doesn’t get rid of these sticky little invisible parasites, and that’s the problem,” Dr. Labia de Latour, a gastroenterologist at NYU Langone, told USA TODAY.
Mordue said washing produce is still a good thing, but not enough to prevent infection.
“We may be able to get rid of some of the Cyclospora, but we can’t get rid of all of them, so there’s still a risk,” Mordue said.
De Latour said the only surefire way to kill parasites is to cook fruits and vegetables. Mordue said frozen fruits and vegetables are also safe because freezing also kills parasites.
Melina Khan is USA TODAY’s national trends reporter. X Keep up with her at @melinakh and on Instagram @bymelinakhan.
