Outbreak of campylobacteriosis at a senior center

In August 1997, campylobacteriosis was diagnosed in four older persons in one Connecticut town. We investigated this outbreak to determine its cause and to identify appropriate preventive measures. We also analyzed surveillance data to assess the impact of campylobacteriosis among persons age 65 years and older in Connecticut.

The outbreak was investigated through a case-control study and an environmental investigation. Surveillance data were from population-based, active foodborne disease surveillance.

The outbreak and environmental studies were conducted at a senior center identified as the one eating place common to all four patients. Active surveillance data were from three Connecticut counties during 1996/1997.

We administered a questionnaire to senior center attendees. A case was defined as onset of diarrhea with fever or abdominal cramps during August 20-25 in a person who ate at the senior center during August 18-20. Respondents without illness meeting the case definition who ate at the senior center during August 18-20 were controls.

Case-control study participants were asked about symptoms of gastrointestinal illness and meals and foods eaten at the center. The environmental investigation gathered information about food preparation procedures and facilities. Active surveillance data were analyzed to determine age-specific annual campylobacteriosis incidence rates and proportions of cases involving hospitalization.

For the case-control study, there were 66 respondents (16 case patients, 50 controls), representing approximately 52% of August 18-20 attendees. Case patients were more likely than controls to have eaten at a Hawaiian luau at the center. The most strongly implicated food was sweet potatoes. Review of food preparation procedures identified multiple opportunities for cross-contamination from raw meats to other foods. In Connecticut's active surveillance area during 1996/1997, the annual campylobacteriosis incidence rate was highest among young adults, but the proportion of hospitalized cases was highest among persons age 70 years and older.

Campylobacter transmission occurred at the luau, likely because of cross-contamination in the kitchen. This investigation emphasizes the importance of strict separation of raw meats from other foods during preparation. Careful attention to these measures is particularly important when an older population is served.