Australian bat lyssavirus for health professionals

Australian bat lyssavirus (ABLV) causes a fatal encephalitis similar to rabies. It is a nationally notifiable disease. We monitor and report on national case numbers. We publish case definitions and guidelines to support health professionals and health authorities.

For health professionals For everyone

Disease

  • Australian bat lyssavirus (ABLV) is a member of the Rhabdoviridae family, genus Lyssavirus. It is closely related to rabies virus, which is also a Lyssavirus. There are 2 known variants of ABLV. [1] [2]

    ABLV is unique to Australia. Any bat in Australia is considered able to carry and transmit ABLV.

  • ABLV infections in humans have a similar clinical presentation to classical rabies.

    Initial (prodromal) symptoms may last from a few days to weeks, and typically include:

    • fever
    • pain or sensory changes at the site of infection
    • malaise
    • headache
    • anorexia (loss of appetite)
    • anxiety.

    One of 2 major clinical forms of disease then develops.

    Encephalitic or furious rabies occurs in about 80%[3] of symptomatic patients and causes:

    • hyperactivity
    • anxiety and agitation
    • hydrophobia (fear of water based on throat spasms during attempts to drink)
    • aerophobia (fear of air due to throat spasms triggered by a draft of air)
    • autonomic overactivity, including hypersalivation, sweating and dilated pupils
    • delirium
    • seizures.

    Paralytic rabies occurs in about one-third of patients. It causes ascending flaccid paralysis of limbs and respiratory muscles but has little impact on consciousness until late in their course of disease.

    ABLV typically causes death from heart or respiratory failure within 1 to 2 weeks of symptom onset.

    Read more about symptoms, diagnosis and medical management of ABLV.

Public health importance

  • ABLV is a public health priority in Australia due to its near 100% fatality rate in humans once symptoms appear.

    Although bat bites and scratches are rare, they require urgent medical management and are associated with significant psychological burden.

    Because of the seriousness of human ABLV infections, we:

  • There have been 4 reported cases of human ABLV infections in Australia – all have been fatal. These cases were reported in Queensland in 1996, 1998 and 2013, and New South Wales in 2025. ABLV became nationally notifiable in 2001.

    The prevalence of ABLV in Australian bat populations is estimated to be less than 1% in healthy bats, but is higher in bats that are sick, injured or orphaned.[4]

    In 2013, ABLV was also detected in 2 horses in Australia.[5]

    For the latest information on human ABLV cases in Australia see the National Notifiable Diseases Surveillance System (NNDSS) data visualisation tool.

Spread of infection

  • ABLV is transmitted to people through exposure to the saliva of infected bats through a scratch or bite. There is currently no evidence of human-to-human transmission of ABLV.

    Other possible modes of transmission, based on rabies virus transmission, include:

    • exposure of mucous membranes (eyes, nose and mouth) to contaminated saliva
    • transplantation of infected tissues or organs.

    Blood, urine and faeces are not considered to be infectious.

  • The incubation period for ABLV is not well-established. It is thought to be similar to rabies virus, which has an incubation period of 5 days to several years (usually 2 to 3 months).[6] [7]

    The incubation period may vary depending on factors such as:

    • the location of the exposure site and proximity to the brain
    • the extent of the injury
    • the size of the virus inoculum
    • existing immunity.

  • The infectious period for humans infected with ABLV is unknown.

Priority populations

Prevention

  • Pre-exposure vaccination is recommended for people who are at greater risk of exposure to the virus through their work or other activities.

    Post-exposure vaccination is recommended for people who may have been exposed to ABLV.

    See the Australian Immunisation Handbook for more information.

  • The best protection against ABLV infection is to avoid contact with bats.

    People should only handle bats if they:

    • have undertaken relevant training
    • have been vaccinated (including recommended booster doses)
    • are using appropriate personal protective equipment.

    WIRES Rescue Line (call 1300 094 737) can refer callers to experts trained in bat handling and rescue in each state and territory.

    If a potential ABLV exposure has occurred, the treating clinician must notify the local public health unit immediately.

    To minimise the risk of infection following a potential exposure to ABLV, treating clinicians must:

    • notify the local public health unit immediately to ensure appropriate post-exposure management – they will advise on wound management, post-exposure rabies vaccination and human rabies immunoglobulin (if indicated)
    • assess the person’s tetanus status (and provide vaccination if required)
    • assess and manage the risk of other potential wound infections.

    To guide the management of the exposure, the public health unit will contact the person to determine:

    • their exposure category
    • past medical history (including immune status)
    • vaccination history.

    The public health unit must also be notified if there is uncertainty about whether an exposure event did occur, including if there was contact with a dead bat. They will contact the person to:

    • gather information
    • undertake a risk assessment
    • determine the appropriate management.

    If the bat involved in the exposure event is available, the public health unit might arrange testing for ABLV.

    See the Communicable Diseases Network Australia (CDNA) national guidelines for public health units for detailed guidance on the management of potential ABLV exposures.

  • Vaccination is the best protection against ABLV for people at greater risk of exposure. This includes any recommended booster doses.

    It is important people handling bats are trained in their safe handling – this includes using appropriate personal protective equipment.

Diagnosis and clinical management

  • ABLV is diagnosed through laboratory testing in symptomatic patients where ABLV is considered as a possible cause.

    The sample used for testing depends on the stage of the disease and may include:

    • saliva
    • cerebrospinal fluid
    • skin biopsy from the back of the neck (nuchal biopsy).

    A specialist microbiologist should be contacted for advice about specimen collection and the testing process.

    Diagnosis may also be made post-mortem using brain tissue.

  • Read more about laboratory testing and the laboratory case definition.

  • Appropriate clinical management is essential to prevent ABLV infection after an exposure event.

    There is no known effective treatment for symptomatic ABLV infection. People with ABLV require hospital-based care.

Notification and reporting

Public health response

  • The CDNA National guidelines for public health units inform the public health response to potential human ABLV exposures and cases.

  • Public health units investigate all confirmed human cases of ABLV and suspected cases where the clinical picture is highly suspicious of ABLV.

    Case management focuses on determining:

    • the likely source of infection
    • the circumstances and type of exposure
    • whether any other people or mammals were also exposed.

    Public health units urgently undertake active case finding for other people who may have been exposed and assess the need for post exposure prophylaxis.

    Urgent veterinary advice should be sought for any exposed animals.

  • Public health units undertake contact tracing of human ABLV cases to:

  • Some situations might require the public health unit to follow up, in conjunction with animal health authorities where indicated. These include where there is:

    • active contact tracing following reports of a confirmed ABLV in a bat
    • a domestic mammal exposed to a bat in Australia.

Resources

References

  • 1 C Deffrasnes, MX Luo, et al., ‘Phenotypic divergence of P proteins of Australian bat lyssavirus lineages circulating in microbats and flying foxes’, Viruses, 2021, 13(5):831, doi:10.3390/v13050831.
  • 2 AR Gould, JA Kattenbelt, et al., ‘Characterisation of an Australian bat lyssavirus variant isolated from an insectivorous bat’, Virus Research, 2002, 89(1):1-28, doi:10.1016/s0168-1702(02)00056-4.
  • 3 TP Scott and LH Nel, ‘Lyssaviruses and the fatal encephalitic disease rabies’, Frontiers in Immunology, 2021, 12:786953, doi:10.3389/fimmu.2021.786953.
  • 4 H Field, The ecology of Hendra virus and Australian bat lyssavirus, PhD Thesis, School of Veterinary Science, The University of Queensland, 2004, doi:10.14264/13859.
  • 5 EJ Annand and PA Reid, ‘Clinical review of two fatal equine cases of infection with the insectivorous bat strain of Australian bat lyssavirus’, Australian Veterinary Journal, 2014, 92(9):324–332, doi:10.1111/avj.12227.
  • 6 World Health Organization, ‘Rabies’, 5 June 2024, accessed 3 July 2025.
  • 7 M Shengli, L Qian, et al., ‘A case of human rabies with a long incubation period in Wuhan’, IDCases, 2020, 23:e00998, doi:10.1016/j.idcr.2020.e00998.

We are adding new content to this website and expanding these pages, including a suite of disease-related information. In the meantime, information about diseases in Australia is available on the Department of Health, Disability and Ageing’s website. 

Last updated: