I want to make an observation and to put up a hypothesis.
When the covid virus first appeared in Wuhan, China, it was lethal. Many people died. It affected mostly the elderly people, but many young people also succumb to the virus.
It move to Italy and cause large fatalities. It then spread to other cities in Europe and America, with devastating results.
A few months later, the virus became less lethal. The death rate came down.
When happened? Here is my hypothesis. I suspect that the virus becomes less harmful over time.
