Thirty-eight outbreak associated cases were detected during this investigation of an outbreak of Campylobacter jejuni infections among football team affiliated individuals in Durand, Wisconsin. Analysis of data pertaining to foods consumed during the team dinner demonstrates that consuming milk during the team dinner was associated with illness. Thirty- eight (100%) ill individuals reported consuming milk during the team dinner and 71% of the ill individuals reported consuming only the Farm A unpasteurized milk.
Farm A bulk tank milk sampled six days after the team dinner was negative for Campylobacter and Shiga toxin-producing E. coli. Cattle can shed Campylobacter and Shiga toxin-producing E. coli intermittently, and contamination of milk may occur during and after milking. The bulk tank milk sample collected on September 24 was not representative of milk that was served during the team dinner. Collection and testing of bovine manure samples proved to be a better method to detect bacteria that were present at the Farm A.
Nine bovine manure samples collected from Farm A were positive for Campylobacter jejuni. PFGE subtyping of Campylobacter jejuni isolates from case attendees detected 3 outbreak associated patterns (Patterns A-C), Pattern A was the predominant pattern identified. PFGE subtyping of Campylobacter jejuni isolates from the bovine manure collected from Farm A also detected Pattern A. The results of the epidemiologic and laboratory investigations conducted by DPH, PCHD, DATCP, WVDL and WSLH determined that consumption of Farm A unpasteurized milk during the Thursday team dinner was associated with the occurrence of Campylobacter jejuni infections among football team-affiliated individuals.