Two people have died as part of the cyclosporiasis outbreak in Michigan, according to the state's Department of Health and Human Services. These are the first reported deaths associated with cyclosporiasis since the outbreak began in May.
The department said in an update on its website Monday that "both individuals had significant underlying health conditions that may have been impacted by cyclosporiasis and dehydration." No other information will be provided on those two cases, according to the department.
Cyclosporiasis usually isn't fatal. Symptoms include watery diarrhea, nausea and fatigue. The Centers for Disease Control and Prevention says most people with a healthy immune system will eventually recover on their own, but the illness can be prolonged.
The illness can be more prolonged and severe in people who are immunocompromised, including cancer patients, people with HIV and people with an autoimmune disease, such as lupus or rheumatoid arthritis, says Dr. Cynthia Sears, an expert in foodborne and intestinal infections at the Johns Hopkins School of Medicine.
The parasite Cyclospora makes its way into the human digestive system in food or water contaminated with human waste.
In Michigan and eight other states, contaminated iceberg lettuce from Taylor Farms in central Mexico has been linked as a source of the outbreak. That lettuce was recalled July 17.
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Cyclosporiasis is usually treated with antibiotics, Sears says. With treatment, she says most healthy people should recover completely within five days.
Without treatment, she says symptoms of cyclosporiasis can appear to clear, only to recur repeatedly. "Even in someone who's perfectly healthy, they can have intermittent diarrhea for weeks to months," Sears says.
Some patients can experience 20 or 30 bouts of diarrhea a day, says Dr. Anurag Malani, an infectious disease specialist and vice chief of medical staff at Trinity Health Ann Arbor Hospital in Michigan. "That can have a profound impact," he says.
Michigan has reported up to 11,234 cases of cyclosporiasis in the current outbreak, though Malani says the true number is likely higher, because many people whose symptoms are milder don't seek testing or treatment.
As of July 30, there have been 193 reported hospitalizations in Michigan. Malani says many of the people he and his colleagues have seen are elderly and have underlying conditions, including cardiac and lung disease, cancer and liver disease.
"I will say that the large, overwhelming majority of people that have cyclospora have done well" and recovered, Malani says.
He says he and his colleagues have seen a marked slowdown in the number of people testing positive for cyclosporiasis compared to three weeks ago, when they were seeing "well over 100 people" a day on some days.
Nationally, the Centers for Disease Control and Prevention counted 6,707 confirmed cases as of July. The number is lower than what states collectively are reporting because of the time it takes for local health authorities to pass information to the federal level and for federal officials to investigate and confirm.
The CDC and the Food and Drug Administration are investigating cases in 45 states. It's the largest cyclosporiasis outbreak on record in the U.S.
Health officials recommend people follow standard food safety handling protocols to protect themselves from the parasite. Cooking fruits and vegetables to 158 degrees F will also kill the parasite.
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