Great and educational read! I also notice how people use polio as their example to why they believe in vaccines and/or how vaccines have changed the world. When I ask them what they know about polio or the vaccination, they have little to no knowledge. You posed a great question, "Why are people so limited in their understanding of polio, yet feel so strongly that vaccines are what eradicated polio? " as well as a great explanation. Thanks for sharing and spreading awareness! Great post