Since 2021, a particularly infectious and deadly strain of avian influenza, highly pathogenic avian influenza (HPAI) A(H5), has been circulating around the globe. Wild birds are carrying higher levels of the extremely contagious virus and bringing it to poultry farms. When a case is detected, it often results in the cull of an entire flock. Last month, it was estimated that the HPAI outbreak has caused the deaths of at least 140 million farmed birds.
Not all birds can be infected with HPAI, but for those that can, the danger is very real. The populations of penguins in South Africa, pelicans in the Balkans, and cranes in Israel have all been impacted and diminished in this outbreak. Many dead birds have been found on UK islands, some of these islands have been closed around Scotland.
“There were just dead birds everywhere,” said Claire Smith, policy officer for RSPB, a UK bird protection organization. “We're not at the end of winter yet, but numbers of deaths are already ahead of last year.”
As of November 2022, in the United States about 58 million cases of HPAI viruses had been identified in wild birds and commercial and backyard flocks.
Demand for eggs is also rising in the United States alongside the disease outbreak, triggering an explosion in prices. The cost of a dozen eggs was up about 60 percent in December 2023 based on prices from a year earlier. More people are turning to backyard flocks. But some veterinarians are recommending that people who maintain poultry flocks should keep them indoors to reduce the spread of avian flu.
Last week, officials in Japan announced that they would cull 10 million birds to stop the spread of avian influenza that country. They expect that the bird flu season will continue until May.
The virus is not showing any signs of abating yet.
There have been very few cases of HPAI in humans, who cannot (yet) spread the virus from one person to another; a person can get infected after contact with an infected bird. In April 2022, a person was infected in the United States, and they recovered. A person was again infected in China in September 2022, and they died from the disease the next month. The World Health Organization keeps a running tally of people infected with avian influenza; between January 2003 and November 2022, there were 868 cases of bird flu in people, and 457 of those cases (53 percent) were fatal. This highlights the low likelihood of infection in people.
However, a case of HPAI was confirmed in a 9-year-old girl in Ecuador on January 11, 2023. She was critically ill and is now in stable condition. The avian flu is spreading in South America too, and many wild birds, particularly pelicans, have died there already.
Health officials are starting to warn doctors to be on the lookout for signs of avian flu in patients, because the virus has real pandemic potential.
It's difficult to try to predict what will happen with a virus. However, this flu has been around for almost twenty years and has not yet found a way to easily spread to people, Ian Barr, the deputy director of the WHO’s Collaborating Centre for Reference and Research on Influenza in Melbourne told The Guardian. It would probably take more than one or two changes for the virus to become transmissible from one person to another, Barr added.
Sources: CDC, World Health Organization (WHO)