EDCP Mission/Vision

Pass the Pit Beef: Lessons Learned from Two Foodborne Outbreaks

Edwards L, Barker N, Burns K, Thompson G, Blythe D, Myers, R.
Epidemiology & Disease Control Program, Maryland Department of Health, Baltimore, MD, Harford County Health Department, Bel Air, MD, and Baltimore County Health Department, Towson, MD.

Background: Pit beef, a central Maryland specialty, is flame-grilled beef that is thinly sliced and is usually served on a bun. Two recent outbreaks of gastroenteritis in Maryland were linked to pit beef and illustrate the need for proper temperature monitoring for grilled meats as well as the need to educate new food-handlers about safe food handling. Persons involved in the first outbreak attended a catered dinner. The second outbreak was identified following a statewide increase in Salmonella montevideo cases in May – July 1999.

Methods: All cases were interviewed about symptoms and food consumption. Stool samples and food specimens were analyzed by culture and pulsed-field gel electrophoresis (PFGE). Environmental inspections were conducted.

Results: In the first outbreak, all 29 dinner attendees ate pit beef. Twenty-four (83%) developed gastroenteritis. Clostridium perfringens was detected in two stool samples and in leftover pit beef. The temperature of the pit beef was not monitored during preparation, transportation to the event site, or during reheating and hot-holding at the event. In the second outbreak, 19 cases of S. montevideo were reported in Maryland between May 1 and July 30, 1999. Nine (60%) of the 15 isolates available for testing demonstrated the same PFGE pattern with two restriction enzymes. Seven of the nine PFGE-pattern matching cases were interviewed. Five of the seven (71%) ate pit beef at the same newly opened restaurant during their incubation period. Testing of employees at this restaurant revealed a S. montevideo-infected food-service worker. Restaurant inspection revealed no thermometers for internal food temperature monitoring and improper cooling of cooked pit beef.

Conclusion: In each of these outbreaks, improper food handling was associated with gastroenteritis among people who ate pit beef. These investigations suggest that pit beef can be a source of foodborne illness and highlight the need for proper temperature monitoring for grilled meats, and proper education of individuals involved in commercial food preparation.

Maryland Department of Health & Mental Hygiene — Epidemiology & Disease Control Program