Production and control of polio vaccines
Poliovirus infection can provide lifelong immunity against the disease, but this protection is limited to the particular type of poliovirus involved (Type 1, 2, or 3). Infection with one type does not protect an individual against infection with the other two types. The development of effective vaccines to prevent paralytic polio was one of the major medical breakthroughs of the 20th century. Two different kinds of vaccine are available:
- An inactivated (killed) polio vaccine (IPV) developed by Dr. Jonas Salk and first used in 1955, and
- A live attenuated (weakened) oral polio vaccine (OPV) developed by Dr. Albert Sabin and first used in 1961.
Both vaccines are highly effective against all three types of poliovirus. There are, however, significant differences in the way each vaccine works as well as their safety and efficacy profiles.