Between September and November, the UK experienced more than 150 cases of avian flu.
This outbreak has led to the death of nearly 100 million poultry birds around the world.
It is threatening wild bird populations in Europe and the US.
Threat: 15 species of seabirds have tested positive for HPAI for the first time.
Deaths have been reported in species like great skuas, which are worrying due to their magnitude and potential to threaten the species’ persistence in the UK.
Avian influenza can be transmitted from animals to humans in two main ways:
Which strain is affecting the poultry right now?
The H5N1 strain of HPAI:
It seems to be more infectious and more fatal to poultry.
It is more persistent in wild bird populations.
It’s also able to affect a greater diversity of species than previous strains.
Avian flu season:
What are the different types of avian influenza?
There are four types of influenza (flu) viruses: A, B, C, and D.
Wild aquatic birds, including gulls, terns, shorebirds, and wild waterfowl, such as ducks, geese, and swans are considered reservoirs (hosts) for avian influenza A viruses.
Subtypes of Influenza A Viruses:
Influenza A viruses are divided into subtypes based on two proteins on the surface of the virus: hemagglutinin (HA) and neuraminidase (NA).
There are 18 known HA subtypes and 11 known NA subtypes.
All known subtypes of influenza A viruses can infect birds, except subtypes A(H17N10) and A(H18N11).
Highly Pathogenic and Low Pathogenic Avian Influenza A Viruses
Avian influenza A viruses are classified into the following two categories:
low pathogenicity avian influenza (LPAI) A viruses: Low pathogenic avian influenza viruses cause either no signs of disease or mild disease in chickens/poultry (such as ruffled feathers and a drop in egg production).
Highly pathogenic avian influenza (HPAI) A viruses: Highly pathogenic avian influenza viruses cause severe disease and high mortality in infected poultry.
Both HPAI and LPAI viruses can spread rapidly through poultry flocks.
Both LPAI and HPAI A viruses have caused mild to severe illness in infected humans.