Berry, Berry, Quite Contrary...Cyclospora Outbreaks

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Outbreaks of illness in the United States causing infectious watery diarrhea, nausea, and vomiting recently have been found to be caused by a parasite called Cyclospora. Food-borne outbreaks of the illness have been reported in the U.S. since the mid-1990s. Most recently, a new outbreak was noted in Iowa when two people were diagnosed with Cyclospora infections (cyclosporiasis) and reported to the CDC on June 28, 2013. This disease was reported to the CDC because the disease has been infrequently documented in the U.S. and is thought to be endemic in some semitropical countries. However, as of July 24, 2013, 285 individuals in 11 U.S. states have been diagnosed with cyclosporiasis with a few others pending diagnosis; 18 people have been hospitalized. The largest numbers have been in Iowa, Nebraska, and Texas.

The Cyclospora parasite is transmitted to people who contact objects contaminated with infected stool (mainly water and foods like fruits and vegetables that may have been washed or sprayed with contaminated water). In 1997, reports of outbreaks of Cyclospora infection were preliminarily associated with the consumption of fresh fruits, such as strawberries and raspberries, but the current outbreaks have not been associated with specific foods.

The Center for Disease Control and Prevention (CDC) works with the federal, state, and local health departments to determine the extent and causes of the recent outbreaks of Cyclospora. They pointed out that although it is prudent to thoroughly wash produce that will be eaten raw, this practice may not eliminate the risk of transmission of Cyclospora. Further, they recommend that health-care professionals consider Cyclospora infection in people with prolonged (longer than about a week) diarrheal illness and specifically request laboratory testing for this parasite.