Vets develop vaccine after first known record of an echidna being allergic to their core food source

Matilda is an unusual echidna. She is curious where her peers are shy, and gregarious where they are solitary. She is also allergic to ants.

For a species also known as the spiny anteater, that is a significant problem. It is the first known record of an echidna being allergic to their core food source.

Keepers at Victoria’s Healesville Sanctuary noticed something was wrong when Matilda, who came to the sanctuary as a three-month-old 700g puggle in 2010, was weaned off milk on to an adult diet of ants and termites. The symptoms became pronounced when she was two years old.

Calling citizen scientists: more data needed to protect echidnas Read more

“She became really puffy and red around both of her eyes, there was a lot of discharge coming from her eyes, and it also affected her belly,” Healesville Sanctuary vet Claire Madden told Guardian Australia. “She lost a lot of hair and also the skin on her belly was really raw.”

Echidnas are prone to various types of dermatitis, usually caused by a parasite like ticks, mites or lice. They can also get secondary skin infections after a traumatic incident like a dog bite or being hit by a car, and also sometimes suffer from dermatitis caused by fungal infections that take hold when they are kept in poor conditions.

Vets at Healesville went through all of those options, trying various topical cures and subjecting Matilda to regular bathing and courses of antibiotics, all of which she accepted with good grace, before veterinary dermatologists at the Melbourne Veterinary Specialist Centre suggested an allergen test.

Facebook Twitter Pinterest Matilda undergoing allergen testing at Melbourne Specialist Veterinary Clinic. Photograph: Amie Hindson/Zoos Victoria

“Even when we did the allergen panel we were not considering ants, but we threw them in there because they are something she is exposed to every day, and it came back that she was allergic to ants,” Madden said. “It was a bit of a shock to us.”

Matilda was also highly allergic to Melaleucas, or paperbark trees, which are common throughout Australia, and is mildly allergic to several other native plants.

“We could not remove ants from her environment because that’s what they are constantly dependant on to survive nutritionally,” Madden said. “So we had to find a way to remove the allergen without removing it from their diet, which is what we would eventually do.”

Australia completes world's largest cat-proof fence to protect endangered marsupials Read more

Veterinary dermatologists developed an individualised vaccine that isolated specific allergen components and exposed Matilda to it in small doses to build up her immune system. She was injected with the vaccine once a week, with the time between vaccines gradually lengthened over a period of four years as her immunity built up.

Her last injection was six months ago. If she continues to be asymptomatic into the start of next winter, she will be introduced into the sanctuary’s breeding program.

Madden said it was possible Matilda’s allergies could be traced to losing her mother at a young age, before she was weaned and before her immune system had fully developed, but it could also be a genetic fluke.

If the allergy is passed on to her puggles, they will be treated in the same way.

Facebook Twitter Pinterest Matilda sniffing a zookeeper’s shoe. She is known for her curious nature. Photograph: Amie Hindson/Zoos Victoria

In the mean time Matilda lives in enclosure near the park’s entrance, which she shares with Snoopy, a 34-year-old female echidna, and a koala named Emily.

Release into the wild is impossible. Even if her keepers could guarantee the allergy was gone for good, she is now too friendly with humans to survive in the wild as a result of conditioning to make her arduous veterinary care as stress-free as possible.

“She has lost the ability to identify that she is in fact an echidna,” Madden said. “She comes up to us and nuzzles our boots and wants to be picked up … we are not allowed favourites here but she is one of our favourites.”