Risk factors for sporadic Campylobacter infections: results of a case-control study in southeastern Norway

TLDR

A 1989–1990 case‑control study in three southeastern Norwegian counties interviewed 52 bacteriologically confirmed Campylobacter cases and 103 matched controls, all infections acquired in Norway. Independent risk factors for sporadic Campylobacter infection were consumption of sausages at barbecues (OR 7.64), daily dog contact (OR 4.26), and eating raw poultry brought into the home (OR 3.20); the sausage risk was not due to poultry cross‑contamination, and poultry from Denmark or Sweden was strongly associated (OR 13.66) whereas Norwegian poultry was not.

Abstract

In 1989 and 1990, a case-control study designed to identify risk factors for sporadic infections with thermotolerant Campylobacter bacteria was conducted in three counties in southeastern Norway. The investigation was confined to infections which were acquired in Norway. A total of 52 bacteriologically confirmed cases and 103 controls matched by age, sex, and geographic region were interviewed. The following risk factors were found to be independently associated with illness in conditional logistic regression analysis: consumption of sausages at a barbecue (odds ratio [OR] = 7.64; P = 0.005), daily contact with a dog (OR = 4.26; P = 0.024), and eating of poultry which was brought into the house raw (frozen or refrigerated) (OR = 3.20; P = 0.024). The risk associated with consumption of sausages at a barbecue could not be attributed to cross-contamination from poultry products. By univariate analysis, consumption of poultry which was brought raw and frozen was associated with illness (OR = 2.42; P = 0.042), even though freezing substantially reduces the number of viable campylobacters. When poultry consumption was examined by country of origin, eating of poultry produced in Denmark or Sweden was strongly associated with illness (OR = 13.66; P = 0.014), whereas consumption of poultry produced in Norway was not (OR = 1.33; P = 0.41).