MMWR Morb Mortal Wkly Rep. 1994 Sep 23;43(37):677, 683-4.
Fiddleheads (crosiers) of the ostrich fern (Matteuccia struthiopteris) are a seasonal delicacy harvested commercially in the northeastern United States and in coastal provinces of Canada. Although some common ferns may be poisonous or carcinogenic, this species has been considered to be nontoxic. However, in May 1994, outbreaks of food poisoning were associated with eating raw or lightly cooked fiddlehead ferns in New York and western Canada. This report summarizes the investigations of these outbreaks.