Avian Influenza Outbreak in the US: Mutation Risks and Prevention Strategies

Avian influenza, commonly referred to as the “bird flu,” is spreading rapidly across the United States. In a recent “Health 1+1” episode, Xiaoxu Sean Lin, a U.S. virology expert and former researcher at the Walter Reed Army Institute of Research, said that human infections with avian influenza were extremely rare prior to 2023. However, Lin [...]

H5N1, which primarily spreads among birds, has nonetheless crossed species barriers, with infections now confirmed in dairy cows, cats, and other mammals, Lin said. This suggests that the virus may be adapting to new hosts. Lin pointed out that while H5N1 is primarily transmitted among poultry, cross-species infections have occurred, spreading to dairy cows, cats, and other mammals.

This suggests that the virus may be adapting to different hosts. He emphasized that if the virus continues to spread within populations, its adaptation to humans could accelerate. The H5N1 virus has acquired mutations at several critical sites, which may enhance its adaptability and ability to infect other species, Lin noted.

Key mutations identified include: PB2 protein: The E627K amino acid substitution has been identified, enabling the virus to replicate more efficiently in mammalian hosts, including humans, pets, and livestock. Hemagglutinin (HA) protein: Mutations in this protein have increased the virus’s binding affinity to host cell receptors, potentially broadening its host range. Neuraminidase (NA): Frequent reassortment events—processes where viruses exchange genetic material— involving the neuraminidase (NA) gene have been observed, which may lead to the emergence of novel recombinant viruses.

$500 million to strengthen biosecurity measures at poultry farms, such as preventing wild birds from transmitting the virus to commercial flocks. $400 million to support poultry farmers, helping those affected by culling to restore their operations. $100 million for vaccine research and the development of treatment options.

Lin noted that China has already implemented a nationwide poultry vaccination program. While it offers partial protection for poultry, it has not prevented outbreaks in the country. Widespread vaccination can lead to viral mutations that enable the virus to evade immunity, similar to what occurred with COVID-19.

Despite global vaccination efforts, the Omicron variant emerged and continued to spread, developing a stronger ability to bypass immune defenses. Monitor the health of poultry Avoid contact with dead birds Avoid consuming raw milk Maintain Good Hygiene.