How Reassortment Could Heighten Bird Flu Risks

Quick Summary

• Influenza Reassortment: Flu viruses can swap genetic material, a process known as reassortment, enabling jumps across species and causing sudden genetic shifts. This mechanism has contributed to at least three of the last four human flu pandemics.
• Prior Pandemics: notable flu pandemics include:

– 1918 H1N1 Great Influenza: killed ~50 million globally.- 1957 H2N2 pandemic: emerged from new gene swaps (avian origin), killed ~1-4 million worldwide.
– 1968 H3N2 pandemic: another reassortment involving avian influenza, caused similar death tolls globally (~1-4 million).
– 2009 swine-flu pandemic: resulted from complex triple-reassorted virus mixing genes from human, swine, avian origins across geographic regions; fatalities ranged between ~151,000-575,000 people.

• Protein-Based Classification: Flu strains are categorized via hemagglutinin (HA) and neuraminidase (NA) proteins-e.g., H5N1 bird flu circulating among wild/domestic birds has not sparked a human pandemic yet.
• Present Concerns:

– sporadic transmission exists among farmworkers exposed to reassorted viruses potentially capable of wider spread later on-modelling historic pre-pandemic symptoms akin openings theorised risks underway may heighten future emergence species/jumps bio-data yr’ sequence tracking complexities science mechanisms.@Charlotte researchers globally Years@.Original