zlacker

But how did one new strain suddenly amass 17 previously unseen mutations?

Normally we should have sampled a number of strains with fewer of the same mutations, shouldn't we?

>>skinke+(OP)
Not an expert here, but there probably are many other strains out there with fewer mutations (and some with more). Most of them residual because they don't provide a clear advantage. The reason we know about this 17-mutation one is that this specific one turned out to have such an advantageous infectivity that it's displacing all other strains and becoming the dominant one.

>>jng+b3
Thanks.

That would make sense, if it was the 17th mutation that (possibly together with the rest of the mutations) gave it this advantage.

>>skinke+(OP)
The problem is most countries don't sample - they put people through a PCR test and then send them off their way. The UK also does somewhat-regular genetic sequencing of positive tests, precisely to spot new mutations.