Facies disease (contagious Tasmanian devil facial tumor)

What is it?

Facies disease is a unique communicable cancer in the world. It only affects the Tasmanian devil, a carnivorous marsupial living in Australia.

Unlike the majority of cancers, this one is not caused by a mutation specific to each individual. The cancer cells themselves are transmitted directly from a sick animal to a healthy animal, much like a parasite would.

This disease forms tumors around the mouth, face and neck. It is almost always fatal and has caused wild populations of Tasmanian devils to drop sharply since its discovery in the 1990s.

Commonly observed signs

These signs are neither exhaustive nor specific. Only a veterinarian can establish a diagnosis.

Causes and risk factors

The disease is caused by living cancer cells that are physically transmitted from one devil to another. These tumor cells, originally derived from a single animal, have acquired the ability to survive and multiply in the bodies of other individuals without being rejected by their immune systems.

Transmission occurs through bites that Tasmanian devils frequently inflict on each other, particularly during group meals or breeding behavior. The cancer cells then pass directly from the wound of an infected animal to a healthy animal.

All adult Tasmanian devils are potentially at risk, as facial biting is a normal social behavior in this species.

Areas with a high population density are more affected, because contact between individuals is more frequent there.

Young individuals who are not yet feeding in groups and geographically isolated populations seem relatively less exposed.

Transmission

Transmission occurs by direct contact, mainly via bites around the face during aggressive social interactions (competition for food, behaviors linked to reproduction). It is not viruses or bacteria that are transmitted, but entire tumor cells.

Diagnosis and care

Diagnosis is the veterinarian's responsibility, based on clinical examination and laboratory tests. Care is decided case by case.

Treatment

There is no effective curative treatment once the disease has established itself in a wild animal.

Depending on the case and the context (animal in captivity, research), surgical intervention to remove a localized tumor may be considered by a specialized veterinarian, but recurrences are common.

Scientific research is actively working on immunotherapeutic and vaccine approaches, which are still experimental to this day.

Prevention

Possible complications

Tumors can invade nearby tissues, prevent the animal from eating normally, cause severe malnutrition and spread to other internal organs.

Breathing difficulties and loss of vision are possible complications depending on the location of the masses.

When to see a veterinarian

Prognosis

The prognosis is very poor once the tumors have taken hold: the progression almost always leads to death within a few months.

In wild animals, no spontaneous recovery has been demonstrated. Only early treatment in a controlled environment (captivity, research) can sometimes slow down the progression locally, without guaranteeing recovery.

Frequently asked questions

References

WOAH — Organisation mondiale de la santé animale (ex-OIE)

Content reviewed by the TunisieVet editorial team · Updated 20 September 2026