There is a low rate of infection in India for unknown reasons.
There is probably less international travel by people from India.
AbE I wonder if it is because in so much of the rest of the world we have our flu shots and our use of anti-biotics to the degree that we do has weakened our auto-immune systems.
I agree with the response by AZPaul3. However, I have wondered about similar possibilities. There are other corona viruses. And perhaps recent exposure to those gives some partial immunity resulting in a milder case of covid-19. And it could be that older people here are more seriously affected, because they are less exposed to those other corona viruses due to meeting fewer other people and fewer school age children.
But this is wild speculation.
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