Molecular and antigenic evolution of H5 and H7 highly pathogenic avian influenza viruses

Authors: LUCZO, JASMINA - Animal Health Laboratory Of Australia; Spackman, Erica

Submitted to: FEMS Microbiology Reviews
Publication Type: Review Article
Publication Acceptance Date: 5/3/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary: Bird flu affects many species of birds and can cause serious disease in poultry. A protein on the surface of the virus called hemagglutinin (HA) is important for determining how severe disease can be and it is the target of vaccines. The HA can also determine how easily bird flu can infect some species of birds. Here we review the literature to compile what is known about how this protein evolved and we survey available sequence to characterize mutations. Certain parts of the HA can mutate more freely than other sections and specific sites are associated with specific amino acids. This data will help map important sites for vaccine development and sites important to identify new strains that may cause severe disease.

Technical Abstract: Avian influenza viruses are ubiquitous in the Anatinae subfamily of aquatic birds, and infection with low pathogenicity avian influenza viruses generally leads to asymptomatic infection or mild clinical disease. In contrast, infection with highly pathogenic avian influenza viruses (HPAIVs) can result in severe disease associated with high mortality rates. Here, we discuss the biology of avian influenza virus, the natural history of HPAIV, the molecular evolution of the hemagglutinin cleavage site motif and the antigenic evolution of HPAIVs. It is crucial to understand the molecular attributes that drive the emergence and evolution of HPAIVs with pandemic potential to inform risk assessments and mitigate the threat of HPAIVs to the poultry and human populations.