6 Nov 2025
Scott Weese said he would buy a beer for anyone who could explain why shortening a course of antibiotics could increase resistance.
Chris Simpson
Job Title
A leading antimicrobial resistance (AMR) expert who challenged traditional thinking around antibiotic course length believes his arguments are “moving the bar” within the veterinary sector.
Speaking at BEVA Congress earlier this year, Scott Weese, director of the Centre for Public Health and Zoonoses and chief of infection control at Ontario Veterinary College’s Health Sciences Centre at the University of Guelph, said he would buy a beer for anyone who could explain why shortening a course of antibiotics could increase resistance.
Prof Weese told the Vet Times Podcast: “I haven’t had anyone come at me with a plausible mechanism.
“I’d be surprised if they could, but I’ve had a lot of people think about it and say, ‘Oh, okay, well that maybe does make sense’.
“[They’re] maybe not completely convinced, but I think we’re moving the bar a little bit.”
He added: “I’m pretty confident I’m not going to have to buy anyone [a beer] for that.”
Joining him on the podcast, Ian Battersby, former responsible pharmaceutical stewardship lead at Mars Veterinary Health and former AMR subject matter expert on Linnaeus’ clinical board, was “completely in agreement”.
He said: “One of the core principles of selecting resistant bacteria is like the principles of Darwin’s selection of the adaptable species, so the longer you leave a selection pressure in place – in this case, it will be an antibiotic – the more likely you are to select for a resistant strain.”
Prof Weese suggested antimicrobial stewardship “has a bit of a bad marketing plan”, while Dr Battersby said it would be helpful “to pitch it as, ‘this is for the best interest of the patient’, not just this doom and gloom message [of] ‘do not use’”.
Prof Weese said recommending against using an antibiotic to a pet owner can be “a lot more powerful” if vets focus on positives beyond just resistance, such as avoiding cost, potential adverse effects and possible issues with administering the drugs. Dr Battersby added: “It is all about optimising care for the patient and minimising risk.”
The pair noted that risk aversion and reluctance to change established behaviour are among the key barriers keeping some vets set in their ways with antibiotic usage.
Dr Battersby also acknowledged that, due to a lack of resources, it can be “very challenging” to conduct large studies showing the effectiveness of shorter courses of antibiotics, but noted that peer-to-peer comparison “seems to be quite a powerful motivator for change”.
Prof Weese said initiatives tracking and comparing antibiotic usage, such as BEVA’s MonitorMe programme, are important for encouraging practices to reduce their usage, adding: “The holy grail for stewardship is good data.”
He said: “We’re not going to get the paradigm-shift studies, but we can maybe get some nudge behaviours. We’ve got all kinds of different ways that we can show and motivate and convince and educate. It just takes a lot of work.”
