There are currently two countries worldwide where polio is endemic. By the way, Rotary International has been fighting to eradicate polio for over 30 years. Polio spreads mainly through human excrement.
Source: https://polioeradication.org/
Photo: https://en.wikipedia.org/wiki/Polio#/media/File:A_displaced_child_receives_a_polio_vaccination_in_UNRWA_shelter_in_Beach_camp_,_Gaza_Strip.jpg