Lol it’s funny you mention polio.
I was reviewing the data and it had pretty much gone away in its own before the vaccine was in widespread use.
Please don't spread misinformation about one of the most successful vaccination campaigns that saved thousands of people per year from being crippled or dead. And especially not during another pandemic in which there already is enough misinformation about vaccines.
https://ourworldindata.org/grapher/prevalence-of-polio-rates...
From what I see, the situation is the same in India - hardly any vaccination and the big 'C' cases have gone down significantly.