Highly pathogenic avian influenza (HPAI) has continued to spread in North America and Europe in recent weeks, with over 40 million domesticated birds affected in the US alone since the beginning of the outbreak.
In the US, 1,635 cases of H5N1 avian influenza have been detected in wild birds in 42 states and over 40 million cases have been found in poultry in 36 states.
Masses of dead birds have washed up on the shores of Maine and Massachusetts in recent weeks, with officials suspecting avian influenza as the cause. The Maine Department of Inland Fisheries and Wildlife issued a statement warning residents against touching or removing dead or dying birds from public areas.
Avian Flu in the UK
Meanwhile, in the United Kingdom, leading scientists from a number of institutions joined forces to form a new research consortium in the fight against bird flu on Monday.
The consortium, headed by the research team at the UK's Animal and Plant Health Agency, received 1.5 million pounds from the Biotechnology and Biosciences Research Council (BBSRC) and the Department for Environment, Food and Rural Affairs (Defra) in order to develop new strategies to tackle future bird flu outbreaks.
The researchers will focus on a number of key issues, such as why current virus strains are creating longer and larger outbreaks, how the virus spreads between different species and wild and domesticated birds, why some birds are more resistant to the flu and developing models to predict how the virus will evolve and spread in the future.
In Norway, highly pathogenic avian influenza was detected in a dead glaucous gull in Longyearbyen on the Svalbard archipelago, the Norwegian Veterinary Institute reported on Thursday. The Institute stressed that this detection is worrying as a number of vulnerable wild bird populations nest in the area during the summer.
The Institute added that, since avian influenza has been seen to infect other animals during the current outbreak, mountain foxes and seals in the area may also be at risk of infection.
Largest outbreak ever recorded
The current outbreak of H5N1 avian influenza, which broke out in Europe last autumn, is the largest ever recorded in North America and Europe, with dozens of species and millions of birds affected over a wide geographical region.
In an opinion published in the American Society for Microbiology journal, European researchers hypothesized that highly pathogenic avian influenza may have become enzootic (meaning infection is maintained in local populations without the need for infection from the outside) in Europe.
The researchers stressed that while in the past winter outbreaks of HPAI usually sharply declined in the summer, this has not been the case since February 2021, as the H5N1 subtype of HPAI increased in late spring, declined during the summer without completely disappearing, and then increasing again in the autumn.
The researchers added that the data currently available suggests a "fundamental shift in the observed epidemiology" of H5N1, which has highly significant implications for both prevention and control strategies as outbreaks become longer and larger. The researchers advised for further investment in next-generation vaccines that can be available at low cost and well-matched to circulating viruses.