Among the many bugs that can cause food poisoning, a microscopic parasite that rides along with imported produce has been a bit of a stranger in Minnesota.
Suddenly the Cyclospora parasite is at the center of two separate outbreaks that have sickened at least 37 people in Minnesota, with more cases expected to be diagnosed in the next few weeks.
Fortunately, using recent advances in laboratory testing, state health investigators were able to quickly identify the cause of the patients’ intestinal discomfort, distinguishing among all the viruses, bacteria and parasites that are likely candidates to make people sick.
As a result of the new testing, state health officials can now track the source of an infection more quickly and take steps to intervene, which could save more people from getting sick.
“In the past, Cyclospora had to be on a clinicians’ radar as to what … somebody would have, and order a specific test for that,” said Trisha Robinson, an epidemiologist supervisor with the Minnesota Department of Health.
A new test at the department’s St. Paul laboratory, also being used by some private labs, including at the Mayo Clinic, quickly screens for many sources of infection, including the Cyclospora parasite.
“It is like one-stop shopping,” Robinson said.
Cyclospora has been relatively rare in Minnesota, which averaged just two cases annually in recent years. Clinics were much more likely to test for norovirus, salmonella or E. coli, which are among the most common types of food poisoning.
Previously, a clinic would need to order several different tests to check for parasites — each one requiring a separate stool sample. It was a lengthy process that required a lab worker, often a microbiologist, to apply a chemical stain to the sample before it could be analyzed.
Now, the lab can run a single test that will detect up to 22 different types of bacteria, viruses and parasites. Each test takes about an hour to run but requires only two minutes of preparation time.
Not only does it improve the ability of the Health Department to find the correct pathogen, it is a timesaver for a busy laboratory that is being asked to run more and more tests each year.
In 2017, the state’s laboratory ran nearly 100,000 tests for infectious diseases of all types, using a staff of 40 workers. It also has 36 employees to screen newborns for 60 serious disorders and another 36 people who do environmental testing on wells, drinking water, air, soil and hazardous waste.
The Cyclospora tests helped uncover one outbreak that has been traced by health officials to Del Monte raw vegetable trays, which have since been pulled off the shelves.
As of last week, 78 people had been infected by the Cyclospora parasite in four states, including 20 cases in Minnesota, where the product was sold at Kwik Trip convenience stores.
A second outbreak sickened 17 people who ate at the Sonora Grill restaurant in south Minneapolis in mid-May. Health Department officials said there is no indication of ongoing risk to patrons.
Kwik Trip and the Sonora Grill did not return phone calls seeking comment on Monday. Health officials said both companies are cooperating with the investigation.
Robin Miller Kroening was among those who got sick in the Cyclospora outbreak. She routinely bought the vegetable platters at Kwik Trip.
“I ate the vegetables all the time. They are packaged and they are clean,” she said. “It is just perfect for lunch size.”
She got sick about a week after having a platter just before Memorial Day weekend. She said she had diarrhea and fatigue so severe it made it impossible for her to work.
“I wasn’t able to eat,” she said. “When I did … my blood pressure dropped down. I thought I was going to have a heart attack.”
Her co-workers convinced her to see a doctor, and about a week after first feeling ill she learned it was Cyclospora.
Miller Kroening has filed a lawsuit against Del Monte.
Her attorney, Ryan Osterholm of the Pritzker Hageman law firm in Minneapolis, said he has more than 50 clients who are linked to the Kwik Trip outbreak. He has also filed a lawsuit in Wisconsin, which has seen about 30 cases.
“I’ve never experienced something like this where so many people are contacting us in such a short amount of time,” said Osterholm.
Osterholm credits the Minnesota and Wisconsin health departments for identifying the outbreak so quickly. He said a Cyclospora outbreak in Iowa in 2013 took more than a month to detect.
Miller Kroening said she is feeling better three weeks after she got sick, but she still gets very tired. And she is wary of buying fresh produce in the store.
“I’m going to switch to organic or start planting my own.”