Campylobacter Jejuni Infections Associated with Raccoon Contact at a Wildlife Rehabilitation Center

BACKGROUND:   In September 2013, the Minnesota Department of Health identified two Campylobacter jejuni cases who reported volunteering at the same wildlife rehabilitation center (WRC). The cases’ isolates were indistinguishable by pulsed-field gel electrophoresis (PFGE). An investigation was initiated to determine whether there was an association between volunteering at the WRC and illness.

METHODS:   A case-control study design was used. Cases were defined as people who volunteered at the WRC during July-September 2013 and experienced fever and diarrhea, or diarrhea lasting ≥3 days, within 1 week of working at the WRC. Controls were defined as individuals who had volunteered at the WRC during July-September 2013. Cases and controls were interviewed about animal species handled, tasks performed, use of personal protective equipment (PPE), disease training, eating and drinking habits at the WRC, and handwashing. Odds ratios and 95% confidence intervals were calculated using logistic regression for binomial variables. T-tests were performed for continuous variables. Pooled animal fecal samples were collected from six different animal locations: avian nursery, waterfowl nursery, laundry room, raccoon nursery, squirrel nursery, and rabbit room.

RESULTS:   Of the 184 individuals enrolled, 18 (10%) met the case definition. In univariate analyses, contact with multiple animal species was significantly associated with illness. In a multivariate model, only direct contact with raccoons was independently associated with illness (adjusted odds ratio [aOR], 12.2; 95% confidence interval [CI], 1.84-80.1; p=0.001). Cases had worked at the WRC a median of 3 months before becoming ill (range, 1 month-4 years). Controls had worked a median of 5 months (range, 1 month-15 years) and a mean of 14 months longer than cases. Only 58% of WRC personnel reported using PPE while handling animals. There were no significant differences in the type or frequency of PPE usage among cases versus controls. Both pooled juvenile raccoon samples tested positive for Campylobacter jejuni; all other pooled animal fecal samples were negative for Campylobacter. The PFGE pattern of isolates from raccoons was indistinguishable from that of the two index case isolates. 

CONCLUSIONS:   This was an outbreak of Campylobacter jejuni infections associated with raccoon contact among volunteers/staff at a wildlife rehabilitation center. Raccoons were identified as the source of infection through a case-control study and through isolation of the outbreak strain of Campylobacter jejuni from raccoon feces. Increased infection control measures and regular training of personnel on zoonotic diseases were recommended, and the importance of PPE usage and handwashing were stressed.