The U.S. Food and Drug Administration is investigating a newly identified outbreak of Cyclospora infections involving at least 72 illnesses, adding another active foodborne disease inquiry while federal health officials continue examining a separate outbreak associated with shredded iceberg lettuce.
The latest outbreak was added to the FDA’s active investigation list after public health agencies identified a group of illnesses believed to share a common source. Investigators have not yet named a specific food, producer, distributor or geographic point of origin connected to the cases.
Federal officials have said the newly announced outbreak is not believed to be related to the ongoing Cyclospora outbreak involving iceberg lettuce. The two investigations are being handled separately, and no evidence has been released suggesting that lettuce is responsible for the additional 72 illnesses.
The FDA has begun a traceback investigation designed to identify foods consumed by infected patients and determine whether those products moved through a shared supply chain. Traceback work can include reviewing purchase records, interviewing patients, examining distribution documents and testing food or environmental samples when they are available.
Cyclospora cayetanensis is a microscopic parasite that causes an intestinal illness known as cyclosporiasis. People generally become infected after consuming food or water contaminated with the parasite. The organism is associated most often with fresh produce that is eaten raw and can be difficult to remove completely through ordinary washing.
Symptoms usually begin several days after exposure and may include frequent watery diarrhea, loss of appetite, weight loss, stomach cramps, bloating, nausea, fatigue and a low-grade fever. Some patients may experience symptoms that continue for weeks or disappear before returning.
The illness does not typically spread directly from one person to another because the parasite must undergo additional development outside the body before it becomes infectious. Contamination is generally believed to occur during growing, harvesting, processing, packing or food preparation.
Cyclospora outbreaks can be difficult to investigate because the incubation period may last up to two weeks. Patients may have consumed numerous meals and several types of fresh produce before symptoms began, making it harder to identify a common food.
Fresh fruits and vegetables also have limited shelf lives and are often eaten or discarded before investigators can obtain samples for laboratory testing. In some cases, the contaminated product is no longer available by the time an outbreak is recognized.
Previous U.S. outbreaks have been associated with foods including lettuce, salad mixes, cilantro, basil, raspberries, blackberries and snow peas. Those earlier cases do not establish the source of the current outbreak, and federal authorities have not advised consumers to avoid any additional food based on the new investigation.
The separate lettuce-related outbreak has been connected to shredded iceberg lettuce distributed through food service channels. Health officials continue working to determine the full scope of those illnesses and whether additional products or locations may be affected.
People experiencing prolonged or severe diarrhea are advised to contact a health care provider. Laboratory testing may be necessary to confirm Cyclospora infection because the parasite is not always detected through routine testing for intestinal illnesses.
The infection is commonly treated with the prescription medication trimethoprim-sulfamethoxazole. Patients who are unable to take that medication may require additional medical guidance because other treatments may be less effective.
Consumers are advised to wash their hands before preparing food, rinse fresh produce under running water and refrigerate perishable items promptly. Washing produce can reduce dirt and some contaminants but may not eliminate Cyclospora completely. Cooking food thoroughly can kill the parasite.
The FDA has not announced a recall connected to the newly identified 72-case outbreak. The agency has also not disclosed whether the illnesses are concentrated in particular states, whether hospitalizations have occurred or when the first known cases began.
Additional details are expected as investigators compare patient interviews, food histories, laboratory findings and distribution records. Until a source is identified, the new outbreak remains an open national food safety investigation separate from the cases already linked to iceberg lettuce.