Maria Foti
Avian influenza, also known as the recently spoken about bird flu, is caused by the influenza A virus. This type of virus is a pathogen that sometimes gets transmitted from wild birds to domestic ones and can on rare occasions be transmitted to humans. As well as birds, some mammals such as foxes and otters, are also catching the disease. This disease is usually spread through contaminated water or feed, or birds’ saliva and droppings.
The UK and Europe have recently seen an outbreak of the avian influenza, with this being the largest-ever recorded outbreak of bird flu in the UK. There have been over 330 confirmed cases since October 2021 across the whole of the country.
The rapid rise in the number of dead poultry is the most obvious sign of bird flu. Several symptoms can be used to recognise the infected birds including blue/purple colouration in a number of different body parts, a swollen head, absence of appetite, and a significant decrease in the production of eggs.
Bird flu has been around for centuries, with professor of virology Paul Digard, saying it originated from ducks in both Asia and Europe. The most widespread strain of this virus is currently the H5N1 virus, which was recorded for the first time in 1996.
What is so unusual about this outbreak?
This outbreak has killed more wild birds than ever before, with sea birds particularly hard hit. Golden eagles and gulls are among the dozens of species that have been found to be infected with the virus.
According to Professor Munir Iqbal, of the Pirbright Institute, “the current virus has affected 80 different bird species.”
Why this outbreak is so much worse than others is a mystery to scientists. It’s possible that the virus has mutated to make it easier for it to spread from bird to bird or to stay in the environment for longer.
So how are we tackling the outbreak?
China has been vaccinating its domestic flocks of birds.
However, other nations have stayed away from this since it is difficult to decide which birds have been immunised and which have not – thus the meat and eggs from immunised groups can’t be sold abroad.
Birds are more at risk of influenza during the months of the fall and winter, so as we move out of these seasons, the risk is expected to be lower and restrictions of bird housing are to be lifted.
For more information on this issue visit:
-Department for Environment, Food and Rural Affairs and Animal and Plant Health Agency, ‘Bird flu (avian influenza): Latest situation in England’, 8 November 2022
-Department for Environment, Food and Rural Affairs and Animal and Plant Health Agency, ‘Bird flu (avian influenza): How to spot it and report it’, 7 November 2022