Highly contagious disease caught from DOGS infects koalas on popular holiday island

Deep coughing has been heard by some of the Victorian islands residents.

Koalas on a remote tourist island have fallen ill to a highly contagious bacterial disease that’s believed to have spread from dogs.

Concerns began in early September when two males presented with what initially looked like pneumonia and later died. They are now thought to have been suffering from advanced stages of the disease which resulted in their lungs being badly affected by mucous.

Locals around Victoria’s Raymond Island then reported hearing strange loud hacking sounds high in the canopy. Rescuers linked the sounds to two more male koalas and they were brought into care and later diagnosed with bordetella bronchiseptica infection, a disease commonly referred to as kennel cough.

Left - a koala in a cage eating leaves. Right - a koala being syringe fed.
Rescuers have treated koalas with kennel cough on Raymond Island. Source: Koalas of Raymond Island

While there have been isolated outbreaks of kennel cough in koalas in Australia’s northern states, it’s a disease that’s been largely unknown in Victoria’s populations. Healesville Sanctuary, which is providing specialised care for the surviving two animals on the mainland, told Yahoo they have not treated the infection in the species before.

What does kennel cough in koalas sound like?

Video filmed of the Raymond Island koalas before their transfer highlights the devastating behavioural symptoms caused by the bacteria, with the animals seen struggling to suppress their coughing fits. All of the ill koalas identified on the island are males, and it's believed this could be because their large mating bellows trigger bouts of deep hacking as they expel air.

In two of the videos below, the frequent coughing sounds are similar to a human cold, while in another the noise is more high-pitched.

Koala victims well-known to Raymond Island carers

While there have been no cases of the disease since September, visitors to Raymond Island are asked to be on the lookout and to report any concerns.

Shelley Robinson heads up Koalas of Raymond Island, a group of volunteers who dedicate their time to caring for local wildlife. Many of the island’s koalas are known to them, including the two koalas who are battling kennel cough, Harlow and Parker.

“Harlow was a joey that we raised and released two and a half years ago,” she told Yahoo. “He’s been a perfect patient because he was hand raised and used to people.”

Shelley is hopeful that with enough time the koalas will be able to return to the island. But treating the koalas has been slow-going as the species is sensitive to antibiotics which can disrupt their fragile gut biome that processes nutrient-poor eucalyptus leaves.

Left - a koala in a cage. Right - a koala being syringe fed.
After initially being treated on Raymond Island (pictured), the koalas were sent to the mainland for specialised treatment. Source: Koalas of Raymond Island
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Tests ongoing as koalas remain in quarantine

Healesville Sanctuary said it could not speculate on whether it expected to see more cases of kennel cough in Victoria, but it agreed to issue a statement about Harlow and Parker’s progress.

“Both koalas are in quarantine, receiving antibiotics and eating well. Both presented with coughing and nasal discharge and bacterial culture confirmed infection with Bordetella bronchiseptica,” Healesville Sanctuary’s Gerry Ross told Yahoo.

“This is not a condition we have seen frequently in Victoria, however, it is reported in Queensland and northern New South Wales and we have been collaborating with our veterinary colleagues there for treatment of these cases.

“The Raymond Island koalas will need to return negative test results to Bordetella before release plans can be determined. They could remain in care for weeks or months depending on their health condition.”

Koalas of Raymond Island is a volunteer-run service that cares for the wildlife in the township. If you would like to find out more about their work, click here.

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