How the novel coronavirus has evolved
So it&#x27;s finally okay to say there&#x27;s multiple strains with different infectiousness and (possibly) severity?<p>Back in February-ish (I forget exactly when), we had confirmed community spread in Washington (West-coast state in the US), with the belief that it had been spreading for weeks and no one noticed, because of how few cases there were, and no bump in hospitalizations.  This was likely the Wuhan strain, which likewise had been spreading in Wuhan for at least a month and a half before it was detected.<p>On the flipside, when it reached Italy, it hit that country hard.  It wasn&#x27;t clear why, but I remember a report sometime during the summer that the most prevalent version of the virus in Italy was distinct from the Wuhan one, and could possibly be labeled a different strain because of its increased infectiousness, that mutation apparently occurring somewhere in Europe and spreading out from there (France was also hit hard at the same time IIRC, but Germany for example was not).<p>Not long after that I remember a cross-country comparison that said the primary version of the virus in New York (US East coast, also hit hard) matched the one in Italy, but not the Wuhan one, and that what we had in Chicago was a mix of the different strains with (at the time) no one winning out over the others.<p>Nice to finally see confirmation about there actually being different strains that are shifting over time, but unfortunately the timing makes it look like lockdowns may have selected for the more virulent version and caused the pandemic to be worse than it otherwise would have been (see the graphs in the &quot;G strains take over&quot; section, where the cases spike only after, well, the &quot;G&quot; strains take over and the Wuhan &quot;L&quot; strain has been pushed out).