the next available HA-sequences from the 30s are rather distant from
A/Brevig/1918, also no virulence as in the 2nd wave
was seen after 1918.
Maybe the virus achieved a new HA in the 3rd wave
or recombined in HA ?
Then the virus fell asleep in ~1949 and awakened in 1977
with a (semi-)pandemic.
The other segments may well have arisen from Brevig/1918 ,
but HA from 1931 looks too much different IMO.
So, what would have happened if the 2nd-wave HA had survived
and no 3rd wave had appeared ? Could that virulent 2nd wave
maybe have reappeared in 1919 and persisted for decades as did H3N2 ?
May that happen with H5N1 ?
I haven't read about this elsewhere, has someone seen it ?
A/Brevig/1918, also no virulence as in the 2nd wave
was seen after 1918.
Maybe the virus achieved a new HA in the 3rd wave
or recombined in HA ?
Then the virus fell asleep in ~1949 and awakened in 1977
with a (semi-)pandemic.
The other segments may well have arisen from Brevig/1918 ,
but HA from 1931 looks too much different IMO.
So, what would have happened if the 2nd-wave HA had survived
and no 3rd wave had appeared ? Could that virulent 2nd wave
maybe have reappeared in 1919 and persisted for decades as did H3N2 ?
May that happen with H5N1 ?
I haven't read about this elsewhere, has someone seen it ?
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