Veterinarians eye reducing antibiotics use in pets

Mars mulls targets; FDA-backed measurement efforts advance

Published: January 10, 2023

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Mars Inc., the world's biggest owner of veterinary practices, is devising goals for its practitioners to cut their use of antimicrobial drugs, as businesses and governments step up efforts to combat pathogen resistance to the medications.

The move comes as annual data released by regulators in the United States, United Kingdom and European Union show that antimicrobial use in food animals is continuing on a years-long downward trend in the wake of rule changes and public-awareness campaigns aimed at agriculture.

More judicious use of antimicrobials, which include antibiotics, is desired because overuse can contribute to antimicrobial resistance, or AMR, which occurs when microbes evolve to withstand treatments meant to kill them, endangering the health of humans and other animals.

Mars, which owns more 2,500 veterinary practices worldwide, said it already has cut antimicrobial use by nearly half at its Europe-focused AniCura division since 2016. AniCura was acquired in 2018 by Mars, which kept AniCura's pre-existing reduction strategy intact.

Other veterinary hospital groups owned by Mars include VCA, Banfield Pet Hospital and BluePearl in the United States, and Linnaeus in the U.K. Whether Mars will set similarly ambitious targets at those businesses remains to be seen.

At least one other corporate consolidator, England's VetPartners, which owns more than 550 practices, mostly in the U.K., has started actively measuring and publicly disclosing its use of antimicrobials.

Mars, based in McLean, Virginia, is a privately held company better known outside of pet circles for making candy. It started measuring its antimicrobial use more closely about 2½ years ago, Dr. Ian Battersby, its head of pharmaceutical stewardship, said in an interview. Once a "current baseline" of use is assessed, the company will set reduction goals in addition to those already in place at AniCura.

The company plans this spring to submit for peer review and publication in a scientific journal an "anonymized, high-level analysis" of its baseline use. Battersby said new targets will be examined on completion of that analysis.

"The data collection and analysis will be repeated annually or biannually so we can track emerging trends in usage," he said. "This will be particularly important, since the initial data-collection period was during the Covid-19 pandemic, and the way medical care was provided changed in different parts of the world during this time."

For example, some countries with stricter lockdowns, Battersby said, introduced remote prescribing, which may have changed thresholds for prescribing.

Contemplating usage reductions can present a conflict for veterinary businesses, which may generate revenue by selling pharmaceuticals in-house. Asked whether Mars would sacrifice revenue by using fewer antimicrobials, Battersby would say only: "Protecting the efficacy of antibiotics for our pets and their owners now and in the future is a responsibility we take very seriously."

In brief

He added: "We are actively working to train our veterinarians to practice good antibiotic stewardship, including through a new educational curriculum on antimicrobial resistance, because preserving antibiotics for when they are really needed helps ensure they remain effective for all."

The sharp declines in usage at AniCura indicate that veterinarians are capable of achieving meaningful reductions. Based in Sweden, AniCura has 450 practices spread across multiple countries on the European mainland. The 50% drop that Mars says it achieved since 2016 is based on point-prevalence studies in dogs. Such studies involve collecting standardized data from many locations at a given moment in time.

For 2021, during one week in October, 190 of AniCura's clinics in 14 countries provided data for 33,544 dogs they examined. Of those dogs, 7.0% received antimicrobials, down from 7.7% in 2020 and 14% in 2016. AniCura aims to reduce that percentage further still — to 5% by 2030.

Battersby said reduction targets at the other Mars businesses may differ, and that it is too early to say if the company would set a company-wide goal.

"Work to reduce antibiotic prescribing is already well underway in some of the regions where we have hospitals, including Scandinavia," Battersby said. "As such, a reduction in baseline usage is likely to look different across countries. It is important that these differences are taken into account before determining if any company-wide targets can be established."

Mars has hired Dr. J. Scott Weese, a zoonotic disease expert at the University of Guelph's veterinary teaching hospital in Ontario, as a paid contractor to advise it on its strategy. (Weese is also a consultant in zoonoses and public health at the Veterinary Information Network, an online community for the profession and parent of the VIN News Service.)

Reduction targets would be achieved by continuing to encourage Mars' around 15,000 veterinarians and 12,000 veterinary technicians to limit usage via educational campaigns and user guides. AniCura, for instance, has produced usage recommendations for surgical antibiotic prophylaxis, wound infections and abscesses, gastrointestinal disorders, skin infections, urinary tract infections, dental procedures, and lower and upper respiratory diseases.

Use of antimicrobials in dogs, cats varies widely

Veterinarians increasingly are being urged to limit their use of antimicrobials in companion animals as the profession attempts to replicate substantial decreases achieved in food animals.

Data released last month by the U.S. Food and Drug Administration show that U.S. domestic sales of "medically important" antimicrobial drugs approved for use in food animals, measured in kilograms of active ingredient, decreased by 0.21% in 2021 from 2020, after a 3% dip the previous year. Medically important drugs are those used in human medicine.

Since peaking in 2015, sales for food animals have fallen by a more substantial 38%, largely owing to the FDA in 2017 banning the use of antimicrobials for promoting growth in livestock. The regulator also prohibited over-the-counter use in animal feed and water, while requiring oversight by veterinarians.

Data released in November by the European Medicines Agency show that across 31 European Union member countries, sales of veterinary medicinal products in 2021 dropped 4.9% compared with 2020. In the U.K., antimicrobial sales for livestock in 2021 dropped 6% versus 2020 to an all-time low, according to its Veterinary Medicines Directorate (VMD).

In companion animals, use of antimicrobials largely has been overlooked, even though it could be an important driver of AMR, according to a review of scientific literature published in October 2021. Consequently, measuring and addressing antibiotic use is attracting more attention. The review paper, for instance, identified 83 studies that have examined antibiotic use in companion animals. An increase in the number of papers published has been especially evident since 2017, occurring primarily in Europe and Australasia.

The FDA, which releases national antimicrobial sales data for the agriculture sector only, recently started funding research at the University of Minnesota College of Veterinary Medicine that is tracking antibiotic use in American pets.

The researchers are collecting data through a series of national point-prevalence studies. One, for instance, found that for 2,599 dogs and cats seen at 52 hospitals around the U.S. on a single day in August 2021, 29% were prescribed at least one antibiotic. That's a far cry from the 7% figure achieved for dogs that same year by Sweden-based AniCura.

Usage varied substantially among AniCura's own individual practices, though, and among the European countries in which it operates. Usage was relatively low, for instance, in Norway, Sweden and Spain and relatively high in France, Belgium and Russia.

In the U.S., the researchers at University of Minnesota also are developing a Companion Animal Veterinary Surveillance Network, which will draw data on antimicrobial prescribing from electronic medical records at the school's teaching hospital and from 115 practices owned by Mars unit Banfield.

The surveillance network is being co-developed by England's University of Liverpool, which built a Small Animal Veterinary Surveillance Network (SAVSNET) that went live in the U.K. back in 2012.

The U.K. generally is more advanced in measuring antimicrobial use in companion animals than elsewhere. As well as SAVSNET, the country also is home to VetCompass, a database operated by the Royal Veterinary College that includes data on about 20 million animals from more than 1,800 participating veterinary practices in the U.K.

Data generated by SAVSNET and VetCompass has provided the basis for various research papers. One study, published in 2016 and based on VetCompass data, found that among 374 British practices, 25% of 963,463 dogs and 21% of 594,812 cats received at least one antimicrobial over a two-year period between 2012 and 2014.

Moreover, unlike in the U.S. and European Union, the British government's annual sales data includes companion animals.

In November, the VMD reported that antimicrobial use in dogs and cats in the U.K. rose in 2021 compared with 2020. Although no reason was offered for the jump, it is broadly accepted that demand for veterinary care has been especially volatile during the pandemic, in part because people in lockdown had more time for pets.

As an illustration of the varying ways in which antimicrobial usage is measured, the VMD calculates a defined daily dose for animals (using the acronym DDDvet) that is based on the average number of days each dog and cat in the U.K. received an antibiotic throughout the year. In 2021, the number of days was 3.1 for dogs, up from 2.6 days in 2020 but down from 4.5 days in 2014. For cats, the number of days rose to 2.4 from 2.1 days, and down only slightly (0.03 days) since 2014.

The U.K.'s VetPartners, which is backed by private equity firm BC Partners, claimed in an inaugural antimicrobial stewardship report released in November that its usage in the first six months of 2022 had fallen 14.3% compared with the same period in 2021. The data included use in large animals. No breakdown was provided between large animals and companion animals.

VetPartners calculated the figure by taking the total volume of antibiotics it purchased and dividing it by the number of full-time-equivalent veterinarians it employed at the time. The company said it bought 3,307 kilograms of antibiotics in the first six months of 2022, or 1.86 kilograms per veterinarian, down from 3,070 kilograms, or 2.17 kilograms per veterinarian, in the first six months of 2021.

The British group also surveyed its practitioners, receiving 289 "usable" responses regarding how frequently they used antibiotics for certain procedures and conditions, such as influenza in cats and diarrhea not accompanied by fever in dogs.

In a press release, the company said it will use the data to see "how we can maybe reduce what we use, or change the antibiotic we use, or replace it with a vaccine or some other healthcare intervention." VetPartners did not respond to a request from VIN News for more detail about the data and whether it will introduce definitive usage reduction targets.

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