Scientists at the University of Glasgow are urging policymakers to reconsider priorities in efforts to understand and control antimicrobial resistance
Antimicrobial resistance in humans is frequently attributed to veterinary use of antimicrobials, but the relative contribution to the problem from animals and humans is poorly understood at the population level. Despite this, proposals are under consideration by the European Parliament to phase out the precautionary (or prophylactic) use of some antibiotics in animals. The plan has been opposed by the British Veterinary Association, which said that the ban would compromise animal health and welfare.
Dr Alison Mather, working with an interdisciplinary research team within the College of Medical, Veterinary and Life Sciences, exploited long-term surveillance data of Salmonella Typhimurium DT104 from co-located humans and animals in Scotland. The findings, published in the Proceedings of the Royal Society B, suggest that the local animal populations are unlikely to be the major source of resistance in humans, and questions policies that restrict the use of antimicrobials in local domestic animals.
Professor Daniel Haydon, Director of the University of Glasgow's Institute of Biodiversity Animal Health and Comparative Medicine said that in the study, there had been significantly more human-only types of resistance than might have been expected if the animal and human microbial communities were well-mixed, suggesting that the risk of resistances passing from animals to humans is lower than previous research has indicated. It was also found that, in the majority of resistances which are common to both animals and humans, the resistances had appeared first in humans.
Professor Stuart Reid, the senior author of the work and now Principal at the Royal Veterinary College, London, added that it remained true that the use of antimicrobials promoted resistance in microorganisms and of course prudent use in all species should still be advocated but the work questioned the, at times, singular focus on veterinary usage.
Whilst the study has focused on a single bacterial species, Reid points out that the findings do demonstrate that we must ensure that our local policies do not impact disproportionately on domestic livestock without considering imported foodstuffs and animals abroad, as well as the medical use of antibiotics. There is still much to be done if we are to understand the problem at the level of the global ecosystem.
Source: University of Glasgow