Lettuce is the primary suspect in a widespread cyclosporiasis outbreak that has led to a significant increase in cases across the United States, with Michigan reporting the highest number of infections. Health officials have not yet identified a specific brand, grower, or supplier of the contaminated produce.
As of July 10, Michigan has recorded 2,640 cases of cyclosporiasis, a 69% increase from the previous Friday. The infection is also on the rise in other states, including New York, Texas, Illinois, Kentucky, and North Carolina. New York City has identified 374 cases between May 1 and July 10 and is also searching for the source.
Cyclosporiasis symptoms can include severe cramping, nausea, vomiting, fatigue, and watery, explosive diarrhea. While some infected individuals remain asymptomatic, others require hospitalization. Health experts advise caution, particularly for immunocompromised individuals, when consuming fresh produce, especially if it is not washed thoroughly at home.
"If you’re not washing your greens yourself, it might be a good idea not to order it at a restaurant or else buy it prepared — especially if you’re immunocompromised," said Dr. Manish N. Trivedi, director of infectious diseases at AtlantiCare. He added that symptoms can be more severe and prolonged for those with compromised immune systems.
Historically, cyclosporiasis outbreaks have been traced to imported foods. However, pinpointing the exact source can be challenging, as contamination may occur at various points in the supply chain. Experts emphasize that cooking produce is the most effective way to eliminate the parasite. For fresh produce that cannot be cooked, thorough washing is recommended, though it may not always be sufficient. "The parasite can be difficult to remove from leafy produce because it may become trapped in folds, crevices, or areas that water does not reach easily," explained Melissa Vaccaro, a senior food safety program specialist at the National Environmental Health Association (NEHA).
Despite the current outbreak, health officials and experts do not recommend a complete avoidance of salads or fresh produce. "Consumers shouldn’t lose confidence in eating fresh fruits and vegetables," Vaccaro stated. "Produce is an important part of a healthy diet." The focus remains on identifying and removing contaminated products to prevent further illness, rather than discouraging the consumption of healthy foods.
Officials are actively interviewing affected individuals to trace the source and are utilizing laboratory testing and public health surveillance to detect and connect cases. "An increase in reported cases doesn’t necessarily mean we’re seeing more contamination," Vaccaro noted. "It also reflects improvements in laboratory testing and public health surveillance that help us detect illnesses and connect cases that might have gone unrecognized in the past."