In April 2014 local and state public health officials in Baltimore, Maryland conducted an investigation of a large outbreak of C. perfringens infections among attendees of the 2014 Food Safety Summit. The event was held at the Convention Center in Baltimore. The primary caterer for the convention center supplied food for the conference.

Investigators identified 216 ill conference attendees. Dates of illness onsets ranged from April 8 to April 12. Chicken marsala served at lunch on April 9 was statistically associated with illness (RR=3.5 (2.0,6.1). The frequency of signs and symptoms, duration of illness, and possible incubation period were consistent with outbreaks caused by C. perfringens. Two specimens submitted by case-patients were positive for norovirus but investigators concluded that norovirus was unlikely to have been the etiologic agent for most illnesses among conference attendees. Stool specimens were sent to the CDC for C. perfringens culture and testing for C. perfringens enterotoxin (CPDE. Specimens were collected too late for culture. Four of 17 stool specimens were positive for CPE toxin.