Farm-level risk factors for fluoroquinolone resistance in E-coli and thermophilic Campylobacter spp. on finisher pig farms

Taylor, N. M., Clifton-Hadley, F. A., Wales, A. D., Ridley, A. and Davies, R. H. (2009) Farm-level risk factors for fluoroquinolone resistance in E-coli and thermophilic Campylobacter spp. on finisher pig farms. Epidemiology and Infection, 137 (8). pp. 1121-1134. ISSN 0950-2688 doi: 10.1017/s0950268808001854

Abstract/Summary

Logistic regression, supported by other statistical analyses was used to explore the possible association of risk factors with the fluoroquinolone (FQ)-resistance status of 108 pig finisher farms in Great Britain. The farms were classified as 'affected' or 'not affected' by FQ-resistant E. coli or Campylobacter spp. on the basis of isolation of organisms from faecal samples on media containing 1 mg/l FQ. The use of FQ was the most important factor associated with finding resistant E. coli and/or Campylobacter, which were found on 79% (FQ-resistant E. coli) and 86% (FQ-resistant Campylobacter) of farms with a history of FQ use. However, resistant bacteria were also found on 19% (FQ-resistant E. coli) and 54% (FQ-resistant Campylobacter) of farms with no history of FQ use. For FQ-resistant E. coli, biosecurity measures may be protective and there was strong seasonal variation, with more farms found affected when sampled in the summer. For FQ-resistant Campylobacter, the buying-in of grower stock may increase risk and good on-farm hygiene may be protective. The findings suggest that resistant organisms, particularly Campylobacter, may spread between pig farms.