You can't read your own reportInformation about the effectiveness of the polio vaccine and how long it provides immunity against poliovirus.www.cdc.gov
Two doses of polio vaccine are 90% effective....
How Well Does the Polio Vaccine Work?Inactivated poliovirus vaccine (IPV), which is the only polio vaccine that has been given in the United States since 2000, protects almost all children (99 out of 100) who get all the recommended doses. For best protection, children should get four doses of polio vaccine.
99 out of 100 isn't 90%