[independentmind]

I understand that. I am not sure that is definitive evidence that the virus has mutated.

The statistics on deaths by age group are really stunning. This may have more to do with the specifics of who was infected, and how, rather than a mutation.

[NautiNurse]

Yes, Italy has a remarkably high elder population. I use the term virus mutation interchangeably with strain. Viruses have a great affinity to mutation, hence a new strain emerges. There are many coronavirus strains/mutations, and the one in Italy is very aggressive.

There are seven general coronaviruses known to infect people. Common viruses include 229E, NL63, OC43, and HKU1. Three others of note: MERS-CoV, SARS-CoV, and our current pandemic SARS-CoV-2.

229E and OC43 are major causes of the common cold. There is no cross-immunity between these two strains, and it is likely that new strains are continually arising by mutation selection.