Americans Are Getting Sick From a Mystery Food—and Investigators Still Can’t Say What It Is

Americans are accustomed to food recalls that name a brand, show a photograph of the package and tell consumers exactly what to throw away.

The current Cyclospora outbreak is more unsettling.

Health officials know that hundreds of people have become ill after eating food in the United States, but investigators still have not publicly identified the specific product responsible.

As of July 9, the Centers for Disease Control and Prevention had received reports of 843 domestically acquired cases in 31 states. Michigan has become a major center of the outbreak, with hundreds of illnesses concentrated in southeastern counties, but the problem extends well beyond the state.

Cyclospora is a microscopic parasite that infects the intestines. It can cause prolonged watery diarrhea, stomach cramps, nausea, bloating, fatigue, loss of appetite and weight loss. Symptoms may disappear and then return, sometimes continuing for weeks without treatment.

Fresh fruits and vegetables are frequent suspects because previous Cyclospora outbreaks have been associated with produce. But Michigan officials said that, as of July 5, no particular grower, supplier or type of produce had been identified as the source of the current outbreak.

That leaves consumers in an awkward position.

They are being warned to use extra care with fresh produce, yet there is no single bag of salad, brand of lettuce or carton of berries that everyone can simply discard.

The Food and Drug Administration is currently investigating multiple Cyclospora outbreaks involving unidentified products. The agency has begun traceback work and product sampling, attempting to follow ingredients backward through restaurants, distributors, processors and farms.

That process can be painfully slow.

Cyclospora symptoms often begin days after a contaminated meal. By the time a patient is diagnosed and questioned, that person may be asked to remember every salad, garnish, sandwich, herb, restaurant meal and piece of fruit eaten during the previous two weeks.

One contaminated ingredient may also have traveled through numerous distributors and appeared in dozens of dishes under different names.

The parasite presents another complication: washing produce can reduce contamination but may not eliminate it completely. Michigan health officials recommend rinsing all fresh produce thoroughly under clean running water and cooking it when practical. Heating food to at least 158 degrees kills Cyclospora.

The outbreak exposes an uncomfortable reality about the modern American food supply.

A single ingredient can be grown in one location, processed somewhere else, shipped through several distributors and served in restaurants or sold in stores across a wide area. By the time illnesses are connected, the original food may already have been eaten, discarded or removed from the supply chain.

For most healthy adults, cyclosporiasis is treatable. But persistent diarrhea can lead to dehydration, and the illness may be more serious for young children, older adults and people with weakened immune systems.

Anyone experiencing prolonged watery diarrhea, severe cramping or unusual fatigue should contact a medical provider and mention the possibility of Cyclospora exposure. Testing for the parasite may need to be specifically requested.

The outbreak is not simply a Michigan lettuce scare, and it is not yet a conventional nationwide recall.

It is something harder to explain and, in some ways, more troubling: a multistate foodborne outbreak in which officials can count the sick but still cannot tell Americans exactly what made them sick.