Polio largely vanished thanks to vaccines. So why is it now back in more countries?

Polio, a potentially disabling virus that’s long been forgotten in many parts of the world, is now circulating in parts of the U.S. and U.K., on the heels of an outbreak in Israel. Medical experts say it’s a wake-up call that the virus still poses a threat to anyone who remains unvaccinated.

source https://www.cbc.ca/news/health/polio-spread-vaccines-1.6547267?cmp=rss