The government lied to us about polio and the polio vaccines:

https://thevaccinereaction.org/2015/06/the-salk-miracle-myth/

Also, there is evidence that certain synthetic chemicals and pesticides caused paralytic disease that was misdiagnosed as "polio":

https://rodneydodson000.medium.com/what-you-didnt-know-about-polio-26d20cba98e5