Michigan parasitic outbreak grows as experts race to identify source

An outbreak of a parasitic gastrointestinal infection called cyclosporiasis, which can cause explosive, watery diarrhea, is growing in Michigan as public health authorities continue to search for the source.

Lynn Sutfin, a spokesperson for the Michigan Department of Health and Human Services, said that as of 4:30 p.m. July 1, more than 225 cases of cyclosporiasis had been identified in at least 21 Michigan counties and the city of Detroit since June 22, affecting people ranging in age from 8 to 84.

But, she said, it remains unclear what the source of the outbreak may be, noting that the U.S. Centers for Disease Control and Prevention and the Michigan Department of Agriculture and Rural Development also are investigating.

State and local health officials are interviewing people who are infected to try to identify a common exposure source. Anyone who recently has been diagnosed with cyclosporiasis is encouraged to report it by calling their local health department.

A health alert was issued June 30 to physicians and other medical providers statewide, asking that they test stool samples from patients who have diarrhea and other symptoms associated with cyclosporiasis. They also are asked to report positive results to their local health departments within 24 hours.

MDHHS said the state Bureau of Laboratories can conduct the tests.

“Outbreaks of cyclosporiasis have been occurring across the United States and now here in Michigan,” said Dr. Natasha Bagdasarian, chief medical executive, in a statement. “Based on the unusual number of cases we have identified in a little over a week, we anticipate additional cases of illness being reported.

“We recommend Michiganders contact their health care provider if they experience sudden, ongoing diarrhea and reach out to their local health department if additional members of their family are suffering from the same symptoms.”

Cyclosporiasis is caused by a microscopic parasite called cyclospora cayatenensis, which is common in tropical and subtropical parts of the world.

Fresh produce imported to the United States from these regions can be contaminated with the pathogen, and people can get sick after eating food or drinking beverages that have been tainted with it. People also can become infected after traveling to parts of the world where cyclospora cayatenensis is endemic and consuming contaminated food or beverages.

Cyclosporiasis does not typically spread from person to person.

According to the Michigan Department of Health and Human Services, symptoms of cyclosporiasis typically begin two to 14 days after exposure and may include:

• Diarrhea that is watery and can be explosive.
• Abdominal cramps and bloating.
• Loss of appetite.
• Weight loss.
• Nausea.
• Low-grade fever.
• Vomiting has been reported as a symptom, although it is less common.

State health leaders urge anyone who is experiencing sudden gastrointestinal illness to be evaluated by a health care provider.

Cyclosporiasis infections can be treated with antibiotics. However, if an infection remains untreated, MDHHS says, the illness could last for days to a month or longer.

Michiganders are urged to take precautions to protect themselves from a cyclosporiasis infection.

Previous outbreaks in the United States have often been linked to imported fresh produce such as basil, cilantro, Mesclun lettuce, raspberries and snow peas, according to the CDC. It also has been identified in people who traveled to cyclospora-endemic areas.

MDARD spokesperson Jennifer Holton said the agency is in the initial phases of its investigation and is collaborating with other agencies to learn about the food history of each person sickened with cyclosporiasis. The plan is to construct an exposure timeline to identify a common source or product.

“There is not a point source identified at this time,” Holton said in an email message to the Detroit Free Press. “Once a product of interest is identified, we will continue to work with our investigative partners and/or lead the formal trace-back process and begin to examine the supply chain.”

In the meantime, MDARD urges Michiganders to take steps to avoid cyclosporiasis and illness caused by bacteria or other organisms, by:

• Washing your hands with soap and water before and after handling or preparing raw fruits and vegetables.
• Washing all fruits and vegetables thoroughly under running water before eating, cutting or cooking.
• Fruits and vegetables that are labeled “prewashed” do not need to be washed again at home.
• Scrubbing firm fruits and vegetables, such as melons and cucumbers, with a clean produce brush.
• Cutting away any damaged or bruised areas on fruits and vegetables before preparing and eating.
• Refrigerating cut, peeled or cooked fruits and vegetables as soon as possible (within two hours).