Info Nugget What should you do if a bat bites you?

The Lyssavirus was first identified in 1996 in a black flying fox in Queensland. Read on to know more about this rare yet deadly virus

What is lyssavirus?

A close relative of rabies Australian bat lyssavirus belongs to the Rhabdoviridae family, the same group of viruses that causes rabies.

It primarily infects bats. Active monitoring suggests fewer than 1 per cent of healthy bats carry the virus, though prevalence rises to 5–10 per cent in sick or injured bats.

In bats, the virus often causes no obvious symptoms, though some show neurological signs such as disorientation, aggression, muscle spasms and paralysis.

Some will die. The virus has been confirmed in all four mainland flying fox species.

Rare, but potentially deadly

Unlike rabies, which causes roughly 59,000 human deaths annually, predominantly in Africa and Asia, human infection with bat lyssavirus is extremely rare. Australian bat lyssavirus, as the name suggests, is unique to Australia.

But other bat lyssaviruses, such as European bat lyssavirus, have similarly caused rare human infections.

Infection & symptoms

Human infection with bat lyssavirus occurs through direct contact with infected bat saliva via bites, scratches or open skin. It can also occur if our mucous membranes (eyes, nose, mouth) are exposed to bat saliva.

If someone has been exposed, there's an incubation period which can range from weeks to more than two years.

During this time the virus slowly moves through the body's nerves to the brain, staying hidden and symptom-free.

Treating the virus during the incubation period can prevent the illness. But if it's not treated, symptoms are serious and it's invariably fatal. The nature of the illness in humans mirrors rabies, beginning with flu-like symptoms (fever, headache, fatigue), then quickly progressing to severe neurological disease, including paralysis, delirium, convulsions, and loss of consciousness. Death generally occurs within 1–2 weeks of symptom onset.

There's no effective treatment once symptoms develop If someone is potentially exposed to bat lyssavirus and seeks medical attention, they can be treated with post-exposure prophylaxis, consisting of rabies antibodies and the rabies vaccine. This intervention is highly effective if initiated promptly – preferably within 48 hours, and no later than seven days post-exposure – before the virus enters the central nervous system.

But no effective treatment exists for Australian bat lyssavirus once symptoms develop.

Best protection

1. Pre-exposure rabies vaccination, involving three doses over one month, is recommended for high-risk groups.

   If you get bitten or scratched by a bat, it's vital to act immediately.

2. Wash the wound thoroughly with soap and water for at least 15 minutes, apply an antiseptic (such as betadine), and seek urgent medical attention.