Rabies virus and Australian bat lyssavirus - including symptoms, treatment and prevention
Lyssaviruses are a group of viruses that include Australian bat lyssavirus and rabies virus and can cause rabies infection in humans.
Classical rabies is a disease of mammals that occurs in many parts of the world, but not in Australia. Rabies can sicken and kill the affected mammal. When people get rabies, usually through a bite or scratch from an infected animal, they almost always die.
Australian bat lyssavirus is carried by bats. It rarely infects humans, but when it does it causes rabies. Only three cases of human infection with Australian bat lyssavirus have been recorded in Australia, all in Queensland: two were recorded in the 1990s and one in 2013. All three people died from the infection.
Rabies (rabies virus and Australian bat lyssavirus infection) is a notifiable condition1
How rabies virus and Australian bat lyssavirus are spread
Both rabies virus and Australian bat lyssavirus are spread from infected mammals to people or other mammals through bites or scratches. Biting or scratching can inject the viruses – which is contained in the animal’s saliva – into the exposed person’s body. An infected animal may not show any symptoms of illness.
Overseas, mammals that transmit rabies include:
- other mammals that can bite and scratch.
Rabies kills many local people overseas and has infected some Australians travelling or living overseas. Rabies is a risk to travellers to:
- Indonesia, including Bali
- others areas in Asia
- the United States of America
- South and Central America
- much of Europe
- the Middle East
- as well as many other places.
In Australia, people who handle bats are at risk of rabies from Australian bat lyssavirus infection. In Australia, bats – both the larger flying foxes (or fruit bats) and the smaller insectivorous (or micro) bats – have been found to carry Australian bat lyssavirus. Scientists believe the virus is present in bat populations throughout Australia.
Signs and symptoms
Rabies virus and Australian bat lyssavirus infection cause similar symptoms. These include:
- malaise (feeling of being unwell)
- sensory changes around the site of the bite or scratch
- an aversion to fresh air and water
- delirium, seizures (fits) and coma.
Death usually follows several days after the onset of symptoms.
Diagnosis can be difficult and confirmation requires laboratory tests for the presence of the virus in skin, blood, CSF (cerebrospinal fluid: the fluid surrounding the brain and spinal cord) and nervous tissue or other tissue.
(time between becoming infected and developing symptoms)
For rabies virus infection, usually 3 to 8 weeks, but periods from 9 days to 7 years have been documented.
There is little information available on the incubation period for Australian bat lyssavirus, but it is probably similar to that for rabies virus.
(time during which an infected person can infect others)
Person-to-person spread is rare, but is possible while the person with rabies remains alive. Animals with rabies may be infectious for several weeks before symptoms appear until after they have died. This period varies depending on the species.
There is no effective treatment currently available for people who have developed signs and symptoms of rabies.
Post-exposure prevention (after any bite or scratch)
If you are bitten or scratched by a bat in Australia, or by a wild mammal (or any unvaccinated domestic animal) overseas:
- Thoroughly wash (for at least 5 minutes) the wound immediately with soap and water. Proper cleansing of the wound is regarded as the single most important effective measure for reducing transmission.
- Apply an antiseptic solution such as povidone-iodine or alcohol.
- Seek immediate medical attention.
- If given soon enough after exposure, rabies immunoglobulin (a solution containing human antibodies specific for rabies that is made from blood products) and rabies vaccine can prevent development of infection. However, once symptoms develop, these infections are almost always fatal.
Pre-exposure prevention (before any bite or scratch)
- Unless it is part of your job and you have been trained in and use the proper protective equipment, do not attempt to handle wild mammals. Rabies is only one of the many infections that animals can transmit to people.
- Rabies vaccine prevents both rabies virus and Australian bat lyssavirus infection. The rabies vaccine is recommended for people:
- who handle or come in contact with bats in Australia including bat carers, wildlife officers and veterinarians
- travelling to countries where rabies is common.
- Rabies vaccine prevents both rabies virus and Australian bat lyssavirus infection.
- It is important to take steps to reduce the chance of animal scratches or bites while overseas, particularly for younger children.
- Travellers are strongly encouraged to discuss the need for rabies vaccination prior to travel with a travel medicine expert. There will be a charge for the vaccine.
- Protecting your health whilst travelling overseas
- Animal bites and scratches
- Staying safe around bats
- When you have a notifiable condition
1 – In South Australia the law requires doctors and laboratories to report some infections or diseases to SA Health. These infections or diseases are commonly referred to as 'notifiable conditions'.