A Case Control Study to Determine Risk Factors for Campylobacter Infection in Christchurch in the Summer of 1992-3

Aim: This study was designed to determine the risk factors for acquiring campylobacter infection in Christchurch in the summer of 1992/3.

Methods: A case control study was conducted of 100 cases and controls from urban areas matched for age and sex. Cases and controls were interviewed by telephone using a questionnaire and results analysed using the Epi Info statistical computer programme.

Results: Eighty one percent of both cases and controls had recently consumed poultry. Eating poultry at a friends house (OR = 3.18, CI 1.0, 10.73, p = 0.03), at a barbecue (OR = 3.00, CI 0.99, 9.34, p = 0.03) or eating undercooked chicken (OR = 4.94, CI 1.03, 23.62, p = 0.05) was a risk whereas eating at home was protective (OR = 0.36, CI 0.14, 0.9, p = 0.02). Other factors associated with increased risk were drinking water from a nonurban supply (OR = 2.7, CI 0.89, 8.33, p = 0.09) or consumption of chicken bought fresh (OR = 1.8, CI 0.85, 3.82, p = 0.10).

Conclusion: Poorly cooked or handled chicken is a significant source of human campylobacter infection. Morbidity may be reduced by increased public awareness and improvement of cooking practices.