Cyclospora

In this image provided by the Centers for Disease Control and Prevention, a photomicrograph of a fresh stool sample, which had been prepared using a 10% formalin solution, and stained with modified acid-fast stain, reveals the presence of four Cyclospora cayetanensis oocysts in the field of view. Iowa and Nebraska health officials said Tuesday, July 30, 2013, that a prepackaged salad mix is the source of a cyclospora outbreak that sickened more than 178 people in both states. Cyclospora is a rare parasite that causes a lengthy gastrointestinal illness. (AP Photo/Centerd for Disease Control and Prevention)

DETROIT (AP) — Two people have died in the cyclospora outbreak in Michigan, state health officials announced Monday, the first deaths confirmed in the U.S. related to the microscopic parasite.

The Michigan Department of Health and Human Services said both people had underlying health conditions that may have been impacted by the intestinal illness and dehydration. The department said it would not provide additional information about the deaths.

Cyclospora is a microscopic, spherical parasite that commonly causes watery diarrhea “with frequent and sometimes explosive bowel movements,” according to the Centers for Disease Control and Prevention. Outbreaks tend to occur most often in the late spring and summer.

The CDC says the illness, called cyclosporiasis, is rarely deadly.

The heat-loving parasite infects the bowels and spreads through feces. In the past, people have been infected by consuming fruits or vegetables that were exposed to feces-contaminated irrigation water.

Dr. Joel Kammeyer, the division chief of infectious diseases at Wayne State University and the Detroit Medical Center, called the deaths a “tragedy” but noted that despite thousands of cyclosporiasis cases, only two people have died.

“For someone who comes into an urgent care and cyclosporiasis is their only issue, it’s relatively easy to treat,” Kammeyer said. But for people who are struggling with other illnesses, he said, “it stands to reason that there are some patients that might not be able to withstand the dehydration that can come with severe cyclosporiasis.”

Cyclosporiasis is less common than other foodborne illnesses, including salmonella and E. coli. Many cases are never linked to a specific food or other source and, for years, few U.S. cyclospora outbreaks were reported. But the number started rising about a decade ago, with a particularly notable spike in 2018 and 2019.

Previously, 2019 saw the most reported U.S. cyclosporiasis cases, with about 4,700.

The CDC said it is aware of more than 18,000 confirmed or suspected cases in the current surge. But CDC numbers can lag state reports, which suggest the number is more than 20,000 nationwide.

Federal health officials have identified lettuce from Mexico served at Taco Bell locations in nine states as a source of the widespread outbreak. As of late July, the number of cases linked to the lettuce was 1,947, including at least 98 people who had to be hospitalized, according to the CDC.

The agency has said other “brands, restaurants, retailers, or distribution channels” could be tied to the outbreak as the investigation continues.


Associated Press reporter Mike Stobbe in New York City contributed.

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