Risk factors for sporadic Campylobacter infection: an all-Ireland case-control study.

We report the findings of the first case-control study conducted in both the Republic of Ireland and Northern Ireland to determine risk factors for sporadic Campylobacter infections. A total of 197 cases and 296 case-nominated controls matched for age, were included. Based on Population Attributable Fraction (PAF), the most important risk factors were consuming chicken [adjusted matched (am) OR 6.8; 95%CI 2.1-21.9], consuming lettuce (amOR 3.3; 95%CI 1.5-7.1) and eating in takeaways (amOR=3.1; 95%CI 1.4-6.6). Contact with sheep (amOR=11; 95%CI 1.6-78), peptic ulcer (amOR=19; 95%CI 3.8-93.7), hiatus hernia (amOR=20.3; 95%CI 2.3-183.3), lower bowel problems (amOR=4.5; 95%CI 1.2-16.8) were also independently associated with infection. Mains water supply showed protective effect (amOR=0.2; 95 CI 0.1-0.9). The findings highlight the continued need for consumer food safety education and further control measures throughout the food chain on the island of Ireland.