Extended-spectrum β-lactamase- and pAmpC-producing Enterobacteriaceae among the general population in a livestock-dense area

Abstract

OBJECTIVES: In the Netherlands there is an ongoing debate regarding environmental health risks of livestock farming for neighbouring residents. This explorative study aims to determine the prevalence of carriage of ESBL/pAmpC-producing Enterobacteriaceae (ESBL/pAmpC-E) in the general population living in a livestock-dense area, and to study associations between determinants, including exposure through contact with animals and the environment, and human carriage of ESBL/pAmpC-E. METHODS: A cross-sectional study was performed among 2,432 adults (aged 20-72 years) in twelve temporary research centres in the south of the Netherlands, consisting of a questionnaire and analysis of a faecal sample to assess carriage of ESBL/pAmpC-E. Risk factors were analysed using logistic regression. RESULTS: The prevalence for carriage of ESBL/pAmpC-E was 4.5% (109/2,432; 95%CI: 3.7-5.4) ranging from 1.4-10.9% among the research centres. ESBL/pAmpC resistance genes were detected in E. coli and K. pneumoniae isolates obtained from these 109 persons and the most common ESBL-resistance genes were blaCTX-M-15, blaCTX-M-14/17, and blaCTX-M-1, originating from 76 participants. Travel in the last twelve months to Africa, Asia or Latin America (OR: 2.82 (95%CI: 1.71-4.63)), having kept cows for a hobby (last five years) (OR: 3.77 (95%CI: 1.22-11.64)), usage of proton-pump inhibitors (OR: 1.84 (95%CI: 1.05-3.23)), and living within 1,000 metres of a mink farm (OR: 2.26 (95%CI: 1.28-3.98)) were identified as risk factors. Exposure to poultry was not identified as a risk factor. CONCLUSIONS: Overall, living in close proximity of livestock animals and farms does not seem to be a risk factor for carriage of ESBL/pAmpC-E.