Frozen chicken nuggets and strips--a newly identified risk factor for Salmonella Heidelberg infection in British Columbia, Canada.

Salmonella enterica var. Heidelberg was isolated from an unusual food source during routine case follow-up, prompting a case control investigation of frozen chicken nuggets and strips. Most frozen nuggets and strips are raw; however, par-frying lends a cooked appearance. As such, suitable food preparation precautions might not be undertaken by consumers. Cases were confirmed in the laboratory between 1 January and 1 April 2003. Controls were generated through forward-digit dialing and individually matched by age category. Telephone interviews were conducted, and limited sampling of unopened product was performed. Eighteen matched pairs were interviewed. The odds of infection were 11 times higher in individuals who had consumed frozen processed chicken nuggets and strips (95% confidence interval, 1.42 < odds ratio < 85.20). One-third of cases and controls considered frozen nuggets and strips to be precooked, and one quarter used the microwave, an ill-advised cooking method. Consumer misconceptions contributed to the risk of infection. Clear labels identifying nuggets and strips as raw poultry are needed.