There are several versions of COVID-19

The 'mutations' existed along side the original from the lab origins.

Q's post suggested the existence of at least two.

So they release the mild but highly contagious version, then they can send an agent to infect targets with the supped-up killer version.

target Trump

target newly elected Republicans

etc

Given the existence of these weapons, Q et al assumed it was best to allow the mild contagious one to spread knowing that it will help ward off the effectiveness of strains that are known to be better at killing.

There are versions to target blacks, Chinese, and other races.

The research started in Israel, but was moved to Wuhan in part.