Vaccines and Preventable Diseases

• Polio Vaccination

  Brief Description

  Polio is an infectious disease caused by a virus that lives in the throat and intestinal tract. It is most often spread through person-to-person contact with the stool of an infected person and may also be spread through oral/nasal secretions. Polio used to be very common in the United States and caused severe illness in thousands of people each year before polio vaccine was introduced in 1955. Most people infected with the polio virus have no symptoms; however, for the less than 1% who develop paralysis it may result in permanent disability and even death.
  
  There are two types of vaccine that protect against polio: inactivated polio vaccine (IPV) and oral polio vaccine (OPV). IPV, used in the United States since 2000, is given as an injection in the leg or arm, depending on patient's age. Polio vaccine may be given at the same time as other vaccines. Most people should get polio vaccine when they are children. Children get 4 doses of IPV, at these ages: 2 months, 4 months, 6-18 months, and booster dose at 4-6 years. OPV has not been used in the United States since 2000 but is still used in many parts of the world.
  
  

  Vaccine Information

  A person is considered to be fully immunized if he or she has received a primary series of at least three doses of inactivated poliovirus vaccine (IPV), live oral poliovirus vaccine (OPV), or four doses of any combination of IPV and OPV. Until recently, the benefits of OPV use (i.e. intestinal immunity, secondary spread) outweighed the risk for vaccine-associated paralytic poliomyelitis (VAPP) which occurred in one child out of every 2.4 million OPV doses distributed. To eliminate the risk of vaccine-associated paralytic poliomyelitis (VAPP), as of January 1, 2000, OPV was no longer recommended for routine immunization in the United States. However, OPV continues to be used in the countries where polio is endemic or the risk of importation and transmission is high. OPV is recommended for global polio eradication activities in polio-endemic countries due to its advantages over IPV in providing intestinal immunity and providing secondary spread of the vaccine to unprotected contacts.