A meta-analysis of case-control studies examining sporadic campylobacteriosis in Australia and New Zealand from 1990 to 2016.

OBJECTIVE We conducted a meta-analysis of case-control studies to identify locally relevant risk factors for sporadic campylobacteriosis in Australia and New Zealand. METHODS We searched Medline, Web of Science, ProQuest and Google Scholar using PRISMA guidelines. Reference lists and grey literature were hand-searched. Meta-analyses were conducted in the R package 'metafor' using published odds ratios and 95% confidence intervals. RESULTS We identified 325 articles, from which we included 10 that described case-control studies. Four risk factors were statistically significant in the meta-analysis: eating undercooked poultry (OR=4.28, 95%CI 3.09-5.93); eating poultry cooked outside the home (OR=2.13, 95%CI 1.66-2.72); having pet chickens (OR=3.29, 95%CI 2.12-5.10); and overseas travel (OR=5.55, 95%CI 3.20-9.63). Among children, having pet dogs showed elevated but not significant risk (OR=1.57, 95%CI 0.99-2.49). CONCLUSIONS We identified consumption of chicken meat and contact with domestic chickens as important risk factors for campylobacteriosis in Australia and New Zealand. Implications for public health: While consumption of chicken meat is a well-known risk factor for campylobacteriosis, zoonotic transmission is often overlooked. This research indicates a greater need for public health awareness surrounding zoonotic campylobacteriosis, especially for young children.