Gastroenteritis associated with oysters.

An outbreak of gastroenteritis occurred in catering students attending three classes at a Yorkshire college in February 1994. The three classes were held on the Monday, Tuesday, and Thursday of the same week and had identical menus. Thirty-seven of the 90 students were affected. A cohort study, with a 94% response rate, showed a highly significant association of illness with the consumption of raw oysters grown in English coastal waters.