Why are there so many new Omicron subvariants, like BA.4 and BA.5? Is the virus mutating faster?

The emergence of new variants has raised questions about whether previous infection offers protection and what the future holdsBy now, many of us will be familiar with the Omicron variant of Sars-CoV-2, the virus that causes Covid. This variant of concern has changed the course of the pandemic, leadin...