Chronic and unregulated use and disposal of antibiotics in animal research facilities contributes to the emergence of drug-resistant superbugs which may pose a threat to human health, according to new research.
A study published in the journal Plos One found that widespread and excessive use of antibiotics, unregulated access to critical drugs and disposal practices in laboratory rodent facilities likely contribute to the global health problem of antimicrobial resistance.
The survey of 95 laboratories in Australia and New Zealand found 71% regularly using antimicrobial agents, which include antibiotics. Common practices included antibiotic dosing of rodent drinking water and inappropriate disposal of medicated water and food.
Lead author Dr Rebbecca Wilcox, a laboratory veterinarian at RMIT and infectious disease researcher, said animal laboratories had unregulated access to antibiotics from veterinary wholesalers and chemical suppliers, and none of the checks and balances required for doctors or vets prescribing them.
Survey responses from laboratory veterinarians and facility managers showed they were using antibiotics that were “not used in other animal sectors” and were “considered drugs of last resort”, she said. “We use them in ways that we can avoid a lot of the time.”
The World Health Organization has named antimicrobial resistance one of the greatest threats to global public health.
Wilcox said antibiotic resistance is “a coming pandemic”.
“This will mean that routine procedures such as hip replacements, knee replacements, caesarean section, surgery for cancer, chemotherapy, will not be feasible. They are going to be life-threatening,” she said.
While the problem of antibiotic use and resistance has been studied extensively in human health and agricultural systems, the Australian-led study published the first empirical evidence worldwide on practices within laboratory rodent facilities.
Most facilities (81%) reported that rodent medicated drinking water was dumped untreated down the drain. Wilcox said this is a concern since wastewater from hospitals and health facilities is a known contributor to antibiotic resistance in the environment.
“There’s a lot of documented evidence that wildlife like seagulls and birds and rats and mice, that hang around wastewater treatment plants, can carry these resistant bacteria and spread them,” she said.
Sanjaya Senanayake, an infectious disease specialist at ANU who was not involved in the study, said deaths from antimicrobial resistance were estimated to reach 10 million a year by 2050, surpassing deaths from cancer. “In a place like the US, you already have about 3 million antimicrobial-resistant infections every year, and about 30,000 deaths are attributed,” he said.
He said the systemic issue had many causes outside the health system. “It’s not just a doctor in a hospital or a family doctor prescribing an antibiotic when they shouldn’t,” Senanayake said. “Most of the antibiotics that are used are not for us, they are used in animals.”
Prof Mark Blaskovich conducts research on the development of new antibiotics and the detection of resistant bacteria at the University of Queensland. He said that while amounts of antibiotics used and discarded at rodent labs were unlikely to be on the same scale as hospitals or antibiotic manufacturers, the facilities offered an interesting “microcosm of the bigger picture.”
“Even with all the controls you have in these rodent facilities, people still don’t use antibodies correctly,” he said. “When people and vets and farmers use antibiotics, very similar things are going on, but on a much larger scale, and it’s really helping to drive the development of these resistant bacteria.”
Wilcox said if animals contract an untreatable bacterial infection, it’s “catastrophic” from an animal welfare perspective, and potential exposure to resistant bacteria is also a health and safety issue for people who work with the animals.
The study found particular cause for concern in cases where a laboratory was next to or part of a hospital, as there could be biosecurity breaches.
Wilcox said she hopes the findings will spark greater awareness and improve practices among the research community, animal ethics committees and policymakers.
“Now that we have some confidence about the actual statistics on this, we can make some recommendations about how to use antibiotics responsibly,” she said.
