Emerging H5N1 Mutations and Their Potential Impact on Human Infections

Emerging H5N1 Mutations and Their Potential Impact on Human Infections

Sub : Sci

Sec : Health

Why in News

Recent cases of H5N1 avian influenza in British Columbia, Canada, and Alameda County, California, have raised global public health concerns. These cases highlight the virus’s potential to mutate, increasing its adaptability to human hosts and raising the risk of human-to-human transmission.

What is the H5N1 virus?

• Influenza A virus subtype H5N1 (A/H5N1) is a subtype of the influenza A virus, which causes influenza (flu), predominantly in birds.
• It is enzootic (maintained in the population) in many bird populations, and also panzootic (affecting animals of many species over a wide area).
• A/H5N1 virus can also infect mammals (including humans) that have been exposed to infected birds; in these cases, symptoms are frequently severe or fatal.
• Ever since it emerged in 1996, H5N1 has resulted in the mass killing of billions of wild birds as well as fowls.
• According to scientists, the virus lacks changes that would make it better adapted to transmit between people and therefore, the risk to human health remains low.
• The potential for influenza viruses to rapidly evolve and the wide geographic spread of H5N1 signals that more human infections should be expected.
• New Clade Emergence: The Avian Influenza H5N1 (clade 2.3.4.4b) emerged in late 2020, leading to a global outbreak primarily spread by migratory birds.
• Millions of birds have died due to the outbreak, and the virus has been detected in over 200 mammalian species, including humans.
• Genomic Findings: Virus belonged to clade 2.3.4.4b, genotype D1.1.
• PB2-E627K mutation identified, associated with: Faster replication in human cells and enhanced adaptation to human hosts.