Polio is a classic public health vaccine. The chance that your child will be exposed to polio while living in the United States is almost zero, and for that reason, the vaccine is not critical in our opinion. For parents who are generally hesitant about vaccines, polio is the least important vaccine on the list. However, part of the reason the risk is so low is that the vaccine is so effective and so many people are protected that our country has excellent herd immunity. To help preserve that herd immunity until the virus has been eradicated from earth, we do recommend the vaccine. We look forward to the day when polio, like smallpox, will be a disease of the past.