A foodborne outbreak of cyclosporiasis caused by imported raspberries
Cáceres, V.M.; Ball, R.T.; Somerfeldt, S.A.; Mackey, R.L.; Nichols, S.E.; MacKenzie, W.R.; Herwaldt, B.L.
Journal of Family Practice 47(3): 231-234
1998
ISSN/ISBN: 0094-3509 PMID: 9752377 Document Number: 496391
An outbreak of cyclosporiasis in persons who attended a luncheon on May 23, 1996, near Charleston, South Carolina, USA, was investigated. In this retrospective cohort study, all 64 luncheon attendees and the chef were interviewed regarding food and beverage exposures. A case of cyclosporiasis was defined as diarrhoea (>=3 loose stools per day, or >=2 loose stools per day if using antimotility drugs) after attending the luncheon. Sporadic cases of cyclosporiasis were also identified and the implicated food was traced. Of 64 luncheon attendees, 38 (59%) met the case definition. Persons who ate raspberries (relative risk [RR]=5.4; 95% confidence interval [CI], 2.2-13.2) or potato salad (RR=1.8; 95% CI, 1.2-2.6) were at significantly increased risk for illness. The population attributable risk percentages were 73% for raspberries and 20% for potato salad. Cyclospora oocysts were found in stools from 11 (85%) of the 13 case patients submitting specimens for testing. It is concluded that the consumption of raspberries (originating in Guatemala) were strongly implicated in the transmission of Cyclospora.