The Centers for Disease Control and Prevention confirmed more than 1,000 new cases of cyclosporiasis in the United States this summer, bringing the total number of confirmed illnesses to more than 17,000.
The cases include 922 hospitalizations and two deaths. Great Lakes states, including Ohio and Michigan, have reported the highest numbers of cases.
Illnesses have been reported in 48 states and the District of Columbia. The exact source of all the illnesses remains unclear, but the CDC said many cases are linked to iceberg lettuce produced in Central Mexico by Taylor Farms.
The company has recalled the lettuce, but the CDC said the products should no longer be available in stores or restaurants because the best-by dates have passed. The agency added that investigators are examining other potential sources of illness.
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The CDC also said 12,000 additional cases are under investigation.
Cyclosporiasis is a foodborne illness caused by a microscopic parasite. People usually become infected through contaminated food or water, especially fresh produce. According to Scripps News medical expert Dr. Omer Awan, the parasite is commonly linked to lettuce, basil and other leafy vegetables.
Symptoms can develop within two to 14 days.
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Common symptoms include watery diarrhea, fatigue and loss of appetite.
