Rabies and Australian Bat Lyssavirus Infection

Lyssaviruses are a group of viruses that includes rabies and bat lyssavirus. Lyssavirus is carried by bats in Australia. Rabies is carried by mammals in many overseas countries. Both are spread by bites and scratches. These diseases can be prevented by rapid and thorough cleaning of the wound and by vaccination. There is no cure.

Last updated: 11 October 2011

What is Lyssavirus?

Lyssaviruses are a group of viruses that includes rabies and Australian bat lyssavirus.

Rabies is a severe viral disease that affects the central nervous system. All warm-blooded animals, including humans, are susceptible to rabies. It is almost always fatal. Rabies occurs in many parts of the world, but does not occur in Australia.

Australian bat lyssavirus is a virus carried by bats. It is related to, but is slightly different from rabies. It rarely infects humans. Only two cases of human infection with Australian bat lyssavirus have been recorded, both in Queensland in the mid-1990s. Both died.

What are the symptoms?

Rabies and Australian Bat Lyssavirus cause similar symptoms. These include headache, fever, malaise, sensory changes around the site of the bite or scratch, excitability, an aversion to fresh air and water, weakness, delirium, convulsions, and coma. Death usually follows several days after the onset of symptoms.

How is it spread?

Both rabies and Australian bat lyssavirus are found in the saliva of infectious animals. The virus is spread to other animals and people through biting and scratching.

Overseas, animals that carry rabies include bats, dogs, cats, raccoons, skunks and monkeys. Australian animals have not been shown to carry rabies.

In Australia, only bats have been found to carry Australian bat lyssavirus - both the larger flying foxes (or fruit bats) and the smaller insectivorous (or micro) bats.

Who is at risk?

People overseas are at increased risk of rabies if they are bitten or scratched by wild animals, or domestic animals that have not been vaccinated against rabies. Rabies infects many local people overseas, and has infected some Australians travelling or living overseas. Rabies occurs in most of the world, but some areas are free of rabies, including Australia and New Zealand.

In Australia, people who handle bats or come into contact with bats are at risk of Australian bat lyssavirus infection.

How is it prevented?

Do not attempt to handle wild animals unless it is part of your job and you have been trained to use the proper protective equipment. If you find an injured or distressed bat, do not attempt to handle it yourself, but call your local wildlife rescue service. Bat lyssavirus and rabies are only two of the many infections that animals can transmit to people.

Rabies vaccine helps prevent both rabies and Australian bat lyssavirus infection. People who should be vaccinated include:

• people who handle or come into contact with bats in Australia - for example, bat carers, wildlife officers, and veterinarians
• people travelling overseas who are likely to come into contact with animals that can bite and scratch.

• thoroughly wash the wound immediately with soap and water
• apply an antiseptic solution such as povidone-iodine to help prevent infection
• see a doctor as soon as possible to care for the wound, and to assess whether you might be at risk of infection.

If you have been vaccinated beforehand you will still need to be revaccinated after a bite or scratch from an infected mammal. However, you will only need two booster shots of the vaccine.

How is it diagnosed?

Diagnosis can be difficult, and confirmation requires laboratory tests for the presence of the virus in skin, blood, spinal fluid, and nervous tissue or other tissue.

How is it treated?

Treatment is supportive. There is no cure once the disease begins.

What is the public health response?

Hospitals and laboratories must notify cases of Rabies and Australian Bat Lyssavirus to the local public health unit. Public health unit staff will investigate the likely source and determine which others may be at risk of infection. Doctors should contact the public health unit for advice on people bitten or scratched by animals or bats that could transmit rabies or Australian Bat Lyssavirus. Public health unit staff will help arrange post exposure vaccine and rabies immunoglobulin where required.