No virologist or epidemiologist will say it is 'usual' that viruses tend to mutate to become less virulent. Perhaps, and even that is contentious, an expert cou

No virologist or epidemiologist will say it is 'usual' that viruses tend to mutate to become less virulent. Perhaps, and even that is contentious, an expert could make a claim for a specific type of virus. This type of reasoning is based on an assumption that a pathogen limits its reproductive number by increasing its virulence. It is reasonable to test this hypothesis, but unfortunately we do not have enough data points to make any conclusive statements.