Polio Immunization

There are two types of polio vaccine: Inactivated (killed) polio vaccine (IPV), which is a shot; and live oral polio vaccine (OPV), which is a liquid that is swallowed.

CDC recommends only IPV, except in very limited circumstances. Children should get 4 doses of IPV at these ages:

  • A dose at 2 months of age
  • A dose at 4 months of age
  • A dose at 6-18 months of age
  • A booster dose at 4-6 years of age

What happened to Oral Polio Vaccine?

Most of you probably remember getting the oral polio vaccine, and may even have gotten it for your older children quite recently.

OPV is an excellent vaccine. Without it we could not have eliminated polio from the western hemisphere, and would not be so close to eliminating it from the rest of the world. Until recently, OPV was recommended for most children in the U.S.

But OPV can also, in some situations, actually cause polio. This is rare, about once in every 2.4 million doses. When the vaccine was preventing thousands of cases of polio a year, having it occasionally cause a case was a small price to pay. But now that the risk of getting polio is extremely low, and because IPV is available, experts have decided that routinely using the oral vaccine in the U.S. is no longer worth the small risk. OPV is still used in parts of the world where the risk of polio disease is much higher.

Four doses of polio vaccine will protect most children for life. However for certain people, for instance, those traveling to countries where polio is still common, a booster dose is recommended.

U.S. DEPARTMENT OF HEALTH & HUMAN SERVICES
Centers for Disease Control and Prevention
National Center for Immunization and Respiratory Diseases