New evidence that amino acid mutations matter for contagiousness

It seems the virus mutated in Europe and became significantly more contagious (though not more dangerous per unit dose):

The Spike D614G amino acid change is caused by an A-to-G nucleotide mutation at position 23,403 in the Wuhan reference strain; it was the only site identified in our first Spike variation analysis in early March that met our threshold criterion. At that time, the G614 form was rare globally, but gaining prominence in Europe, and GISAID was also tracking the clade carrying the D614G substitution, designating it the “G clade”. The D614G change is almost always accompanied by three other mutations: a C-to-T mutation in the 5’ UTR (position 241 relative to the Wuhan reference sequence), a silent C-to-T mutation at position 3,037; and a C-to-T mutation at position 14,408 that results in an amino acid change in RNA-dependent RNA polymerase (RdRp P323L). The haplotype comprising these 4 genetically linked mutations is now the globally dominant form. Prior to March 1, it was found in 10% of 997 global sequences; between March 1- March 31, it represented 67% of 14,951 sequences; and between April 1- May 18 (the last data point available in our May 29th sample) it represented 78% of 12,194 sequences. The transition from D614 to G614 was occurred asynchronously in different regions throughout the world, beginning in Europe, followed by North America and Oceania, then Asia (Figs. 1-3, S2-S3).

That is from a new paper in Cell by B. Korber, via Eric Topol.  You will note there is another recent paper suggesting the east and west coasts of the United States have faced different mutations and thus different levels of contagiousness, but that seems less well established.

The authors do not mention Taiwan, but if I understand their chronology correctly, it would seem that Taiwan has not significant been hit by the most contagious version of the virus.

In any case, I will repeat my general point: moralizing about the virus is premature.  And of course the main result presented in this new paper is subject to revision, further scrutiny, and possible reversal.

Addendum: Here is NYT coverage.


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