I& #39;m afraid this is a naive view on the virulence / transmissibility tradeoff in pathogens. A reduction in virulence is only expected to happen in strictly vertically transmitted pathogens (e.g. mother to child), where the pathogen and host fitness are strictly linked.
(1/5) https://twitter.com/MLevitt_NP2013/status/1276793878440562688">https://twitter.com/MLevitt_N...

Under horizontal disease transmission, as is the case for epidemic pathogens such as #SARSCoV2, essentially any evolutionary trajectory is possible. Evolution of virulence depends on host population structure, and within-host viral replication, among other things.
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#SARSCoV2 is not lethal enough to be under strong selection for reduced virulence. The small proportion of hosts killed won& #39;t significantly affect its transmission. Besides, transmission of #COVID19 tends to happen early in the infection, sometimes before symptoms.
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The burden of #COVID19 will decrease over time as immunisation in the population builds up through infection/vaccination. Though, there is no particular reason to believe #SARSCoV2 will become intrinsically more/less virulent/transmissible.
(4/5)

There is no convincing evidence suggesting #SARSCoV2 has become more/less transmissible/virulent since it jumped into humans in late 2019. The mutations acquired by the global viral population until now are apparently all & #39;segregating neutrally& #39;.
(5/5)
https://doi.org/10.1101/2020.05.21.108506">https://doi.org/10.1101/2...