US sees thousands of cyclosporiasis cases

Cyclosporiasis is a disease caused by the parasite cyclospora and is most common during the spring and summer months. People can be infected with the parasite if they consume food or water that's been contaminated with feces.

Symptoms of the disease include cramps, nausea, loss of appetite, vomiting, fatigue, diarrhea, body aches, low-grade fever, and other flu-like symptoms. Cyclosporiasis can last for a few days to over a month, and symptoms can come in waves, returning more than once after going away.

So far, CDC has reported 1,645 confirmed cases of cyclosporiasis and 141 hospitalizations across 34 states. However, the true number of cases is likely much higher, with the agency investigating over 5,100 additional illnesses that may be linked to the parasite.

Michigan is currently reporting the highest number of cases (4,312) and hospitalizations (102). Three other states — Ohio, West Virginia, and Kentucky — have also reported more than 400 cases. Other states with higher-than-usual cases of cyclosporiasis include North Carolina, Illinois, Indiana, Maryland, and Texas.

According to Caitlin Rivers, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health, the United States is on track to see more cases of cyclosporiasis this year than any other year on record. Since 2016, CDC has reported an average of roughly 2,800 cases of cyclosporiasis per year nationwide. 

Although federal health officials did not identify a supplier, two individuals familiar with the situation named Taylor Farms, one of the country's largest producers of fresh lettuce and other vegetables, as the supplier. Taylor Farms' produce can be found in salad kits at several major grocery stores, and it is a leading supplier of produce for many large restaurant chains.

Initially, FDA reported that it had identified cyclospora in a sample of iceberg lettuce from Taylor Farms de Mexico. However, the agency later walked back the finding, saying it was a false positive and that "there are not confirmed positive sample results for product testing for Cyclospora" as of July 19. 

"The investigation remains active, and additional states, restaurants, retailers, or products may be identified as more information becomes available," said Emily Hilliard, an HHS spokesperson.

How to protect yourself against foodborne illness

Amid the ongoing outbreak, health experts have emphasized the importance of food hygiene and handwashing to reduce the risk of foodborne illnesses. Some tips include:

• Washing your hands thoroughly for at least 20 seconds with hot, soapy water before prepping fresh fruits and vegetables
• Peeling or removing the outer layer of fruits and vegetables, like the rind of a watermelon or the outside layer of a head of lettuce
• Avoiding damaged or bruised produce
• Keeping produce cold in storage, ideally for a short amount of time
• Thoroughly cooking any food or produce before eating

Buying produce from local farmers' markets may also help reduce the risk of exposure to the cyclospora parasite behind the current outbreak. According to Vox, prior outbreaks have been linked to produce grown elsewhere, either in the United States or internationally, and shipped long distances to grocery stores.

"Single-source produce from a local farm with good manufacturing/farming practices in place, with a safe water supply, are good," said Rosemary Trout, a food scientist at Drexel University. "Commercially processed, pre-packaged foods are likely combining produce from various farms, which may increase risk, despite good manufacturing practices in place."