The outbreak of parasitic infections linked to Fresh Express bagged salad totals nearly 700, with states in the Midwest particularly hard hit. The case total as of August 14, 2020 is 690 individuals infected in the U.S.
Laboratory-confirmed Cyclospora infections associated with this outbreak have been reported from 13 states: Georgia (1), Illinois (209), Iowa (206), Kansas (5), Massachusetts (1), Minnesota (86), Missouri (57), Nebraska (55), North Dakota (6), Ohio (4), Pennsylvania (2), South Dakota (13), and Wisconsin (45). The ill person from Georgia purchased and ate a bagged salad product while traveling in Missouri.
The Food and Drug Administration (FDA) indicates that illnesses started on dates ranging from May 11, 2020, to July 20, 2020. Ill people range in age from 10 to 92 years with a median age of 57; 51% are female. Of 680 people with available information, 37 people (5%) have been hospitalized. No deaths have been reported. It takes an average of 2 – 4 weeks for signs of illness linked to Cyclospora to be reported, and authorities believe that additional cases may appear. In addition to the outbreak involving Fresh Express bagged salads, the Centers for Disease Control and Prevention (CDC) is also investigating a Cyclospora outbreak of domestically acquired cases. As of July 29, 2020, the CDC has reported an additional 779 laboratory-confirmed cases of cyclosporiasis in 28 states that may, or may not, be related to the outbreak linked to bagged salads.
What are the symptoms of cyclosporiasis illness and what causes the disease? Cyclospora cayetanensis is an intestinal parasite. People can become infected with Cyclospora by consuming food or water contaminated with feces (stool) containing the parasite; it is unlikely that Cyclospora is passed directly from one person to another.
Cyclospora infects the small intestine (bowel) and usually causes watery diarrhea, with frequent, sometimes explosive, bowel movements. Other common symptoms include loss of appetite, weight loss, stomach cramps/pain, bloating, increased gas, nausea, and fatigue. Vomiting, body aches, headache, fever, and other flu-like symptoms may be noted. The CDC has a fact sheet explaining the illness and treatment (web page in Spanish).
How is Cyclospora different from other foodborne pathogens such as Salmonella? Bacteria such as Salmonella are very simple, single-celled life forms. Bacteria can grow in food when conditions are right, or in the human or animal gut if live cells are ingested. Cyclospora is an intestinal parasite, a complex one-celled organism with cells very similar to human cells. While the cells of Cyclospora can not grow in food, contaminated food may be a vehicle or carrier for the parasite and, once ingested, the parasite can multiply rapidly in humans. Food or water carrying contaminated human feces is the route by which the illness spreads. The investigation into contaminated bagged salads suggests that water from a canal used to irrigate fresh lettuce was contaminated with the parasite, leading to the ongoing foodborne illness outbreak.