Avian influenza in humans (bird flu)
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Fact sheet - Health conditions directory
Australian CDC fact sheets
Avian influenza (bird flu) is caused by types of influenza A viruses, similar to the virus that causes flu in humans. Avian influenza viruses (AIV) mainly infect birds. AIV are described as high pathogenicity avian influenza (HPAI) or low pathogenicity avian influenza (LPAI) depending on the severity of disease in poultry.
In Australia, LPAI viruses are commonly found in wild aquatic birds, usually without causing apparent signs of disease. Occasionally, LPAI strains evolve into HPAI strains when they spread among poultry and can cause severe disease and death of poultry.
The emergence of the high pathogenicity avian influenza (HPAI) H5N1 clade 2.3.4.4.b has led to extensive losses of poultry and wild birds and mammals, particularly marine mammals globally. It has also been reported in dairy cattle, alpacas and goats.
This strain has spread rapidly between continents associated with the movement of wild birds. In June 2026, Australia confirmed its first detections of HPAI H5N1 clade 2.3.4.4b in seabirds.
Human infection is rare, but can occur after close contact with infected birds, other animals, contaminated environments or contaminated objects.
Avian influenza is monitored by animal and human health authorities.
Public health management guidelines
Notification
Attending medical practitioners/medical superintendents (or delegates)
Pathology laboratories
- Notification criteria for pathology laboratories (PDF, 55kB)
Notification resources
- List of all Pathological, clinical and provisional diagnosis notifiable conditions
- List of Public Health Unit contacts
- Notifiable conditions report form for Queensland doctors/clinicians (PHA S70) or person in charge of a Hospital (PHA S71) (PDF, 77kB) - if faxing notification, follow up by phone.
Enhanced surveillance for public health units
- Case report form (PDF, 388kB) - used by public health units to collect and manage more detailed information for enhanced case surveillance.
Resources for health professionals
- Australian Government Department of Health Disability and Ageing -
Avian influenza in humans (bird flu) - Australian Centre for Disease Control - Bird flu (avian influenza) for health professionals
- Department of Agriculture and Fisheries - Avian influenza (bird flu)
- Queensland Government | Business Queensland - Avian influenza (bird flu) alert - for industries
- Communicable Diseases Network Australia - National guidelines for avian influenza - protecting people who work with birds and wildlife
- Australian Immunisation Handbook: Commercial poultry and pork industry workers are recommended to receive influenza vaccine during an outbreak of avian or swine influenza | The Australian Immunisation Handbook
- Wildlife Health Australia: H5 bird flu resource centre
- High pathogenicity avian influenza information - H5N1 global outbreak (wildlifehealthaustralia.com.au)
- World Organization for Animal Health information system – Latest avian influenza outbreak information
- World Health Organization Global Influenza Programme Human-Animal interface - Risk assessment summaries and situation reports for influenza at the human-animal interface
- Results of Influenza Risk Assessment Tool | Pandemic Flu | CDC - Support for the risk assessment of avian influenza viruses with pandemic potential