Skip to main content

Avian influenza is a highly contagious viral disease. It affects the respiratory, digestive or nervous system of many species of birds.

First published:
6 December 2018
Last updated:

Current restrictions

Avian Influenza (bird flu) in poultry and other captive birds

Avian influenza is an infectious disease caused by influenza A viruses. It affects poultry and other captive birds, although waterfowl may show few or no signs of disease. The risk of avian influenza in Great Britain is greatest during the winter months, when migratory wild birds, particularly ducks, geese, swans, and gulls, can introduce the virus.

Avian influenza viruses are classified according to their ability to cause disease (pathogenicity). They are either highly pathogenic or low pathogenic.

Highly Pathogenic Avian Influenza (HPAI)

HPAI spreads rapidly and can cause severe disease with high mortality rates. Infection may result in sudden death and widespread outbreaks.

Low Pathogenic Avian Influenza (LPAI)

LPAI usually causes mild disease or no obvious clinical signs. However, disease severity may increase when birds are affected by stress or concurrent infections. Some LPAI viruses can evolve into highly pathogenic strains.

Report a suspicion

Contact your local Animal and Plant Health Agency (APHA) office immediately on 0300 303 8268 if you suspect avian influenza.

APHA vets will investigate suspected cases.

If the disease is confirmed, the outbreak will be controlled in line with the contingency plan for exotic notifiable diseases. The control strategy for notifiable avian diseases (on gov.uk) will be implemented.

Clinical signs

The following clinical signs may be present:

  • swollen head
  • blue discolouration of the neck and throat
  • loss of appetite
  • respiratory distress such as: gaping beak, coughing/sneezing, gurgling
  • diarrhoea
  • fewer eggs laid
  • increased mortality

Transmission and prevention

Although Avian influenza is a disease of birds, in rare cases humans can become infected. Some strains of Avian influenza can spread easily and quickly between birds and have a high death rate.

All bird keepers must:

  • continue to practice the highest levels of biosecurity
  • be vigilant for any signs of disease

Biosecurity advice

Strict biosecurity is the most effective way to prevent avian influenza.

All bird keepers are urged to maintain high levels of biosecurity; whether you have a few pet birds, or if you have a large commercial flock.

To ensure high levels of biosecurity, all poultry keepers should:

  • minimise movement of people in and out of bird enclosures
  • clean and disinfect footwear using a government approved disinfectant, and keep areas where birds live clean and tidy
  • ensure the areas where birds are kept are not attractive to wild birds, for example, by netting ponds and by removing access to food sources
  • keep your birds separate to and without access to areas where especially geese, ducks and gulls are present
  • feed and water your birds in enclosed areas to discourage wild birds
  • clean and disinfect vehicles and equipment that have come into contact with poultry, and reduce any existing contamination by cleansing and disinfecting concrete areas
  • keep a close watch on birds for any signs of disease and report any sick birds or unexplained deaths to your vet or APHA

Legislation