Drug-resistant hookworm found in growing number of retired greyhounds

Deadly superworm leaves retired greyhounds waiting months for homes Sat 18 Jul 2026 at 7:09am In short: A growing number of retired racing dogs are infected with a deadly treatment-resistant parasite, according to greyhound adoption groups and veterinarians. The parasite can survive standard worming medication that normally would eliminate it. Specialist vets have raised concerns about animal welfare, adoption costs and the spread of the disease beyond the racing industry. Greyhound adoption groups and specialist vets say they're seeing a growing number of retired racing dogs infected with a deadly treatment-resistant parasite. Concerns have been raised about animal welfare, adoption costs and the spread of the disease beyond the racing industry. Treatment-resistant hookworm, like any worm infection, is transmitted through dogs when they ingest larvae from contaminated soil, faeces or eating other infected animals like rodents. The parasite can survive standard worming medication that normally would eliminate it, with infections causing gastrointestinal issues like chronic diarrhoea, anaemia and in some cases death. Tweed Heads vet Dr James Routledge has spent decades treating greyhounds and said treatment-resistant hookworm had become increasingly difficult to manage. "In the old days, we simply wormed them and the problem was solved," Dr Routledge said. "But resistance has been rising and now that's become quite an issue, quite difficult." Dr Routledge said he first encountered treatment-resistant hookworm in a greyhound puppy in the late 1980s and had watched resistance develop to successive generations of treatments over decades. "We've always had a newer family of anthelmintics to rescue us," he said. "We're now at the stage where the only one that seems to work is difficult to get hold of." Dr Routledge said a new treatment available was being made in Ukraine, but was in short supply due to supply chain issues caused by the war and demand for the medication in other countries. "The same problem that I've alerted everyone to here that's been emerging on the east coast of Australia is happening in the USA too," he said. "Any supply that is made is quickly consumed by this issue." Dr Routledge said while greyhound trainers and breeders had been proactive in ensuring their dogs were wormed, the industry naturally lends itself to hookworms developing drug resistance. "The most common sort of situation where you see large numbers of dogs housed together on sand or soil just happens to be the greyhound breeder and trainer," he said. "That substrate is the ideal substrate for any hookworm eggs and larvae to survive and then reinfect. "If [the hookworm] keeps getting exposed to [treatment], in the same way as antibiotics in humans as well, the more you get exposed to something, those that happen to have the ability to survive it will then dominate the population and that drives resistance." Friends of the Hound, a greyhound rescue charity, said it had conducted 110 faecal tests across 34 retired racing greyhounds entering its care this year. 21 of those dogs tested positive for treatment-resistant hookworm. The organisation said it was still treating 13 infected dogs, with some requiring repeated testing every two weeks and months of treatment before they could safely be adopted. President Lisa White said the rescue group had already spent more than $12,500 on testing and treatment since January. "It's a difficult to treat parasite, which is creating significant animal welfare and financial concerns to our rescue group and adopters," she said. "Responsible rehoming is taking months and months before the dog can go to a home. "And it has serious risk for dogs and owners in the wider community." The comments come after a 2025 study from the University of Queensland found almost 70 per cent of the hookworm samples studied showed genetic mutations that could cause drug resistance. Friends of the Hound and animal welfare organisation Animals Australia are calling for mandatory routine faecal testing throughout a greyhound's racing career, mandatory treatment for infected dogs, and nationally consistent guidelines for managing treatment-resistant hookworm. "The uncontrolled spread of drug-resistant hookworm requires urgent action from the racing code, transparent reporting and independent research which should be funded by greyhound racing," Animals Australia director of corporate and government relations Jo Webb said. "Sadly, it is yet another example of poor animal welfare perpetuated by racing." Dr Routledge said broader surveillance would also be needed to better understand how widespread resistant infections had become. "We first need to get a handle on what the problem is," he said. The Queensland Racing Integrity Commission (QRIC), which is responsible for the health of racing greyhounds in the state and also runs the Greyhound Adoption Program, said while the welfare of racing animals is the primary responsibility of owners and trainers, it enforced rule obligations. "QRIC provides guidance to industry participants on maintaining effective worming programs, including the correct use of commercially available treatments," they said. "Hookworm resistance is a recognised issue across the broader Australian dog population and is not unique to racing greyhounds. "QRIC is working with a parasitologist at The University of Queensland's School of Veterinary Science to undertake targeted testing through the Greyhound Adoption Program (GAP), including faecal egg counts, resistance monitoring and DNA screening." The commission said they were working on expanding race-day sampling and voluntary testing at trainer kennels and were about to commence another trial in collaboration with Murdoch University focused on developing greater hookworm resistance.