The parasite Cyclospora was first described by Dr. Ashford, a British parasitologist, in 1979. He found the parasite in stool samples from sickened people in Papua New Guinea in 1977 and 1978. In the 1990s, Cyclospora garnered increasing interest from the scientific and public health communities after it was identified as the cause of outbreaks of diarrheal illness in the United States. Since then, scientific understanding of Cyclospora’s source and infectious process has grown substantially.
Humans contract Cyclosporainfections from eating food or drinking water contaminated with Cyclospora. Contamination of food often occurs when produce is irrigated or washed in water contaminated with human feces. Cyclospora uses the human body to complete part of its reproductive life cycle.
Cyclospora is not endemic to the United States. The illness is most common in tropical and subtropical regions, and it is more common in summer months. Numerous previous outbreaks of Cyclosporain the United States have been associated with consumption of fecally-contaminated fruits and vegetables, including raspberries, mesclun, basil, lettuce, and cilantro.