What type of vaccine is the Oral Polio Vaccine?

The Oral Polio Vaccine (OPV) is classified as a live attenuated vaccine. This type of vaccine contains live, but weakened, forms of the virus that cannot cause disease in healthy individuals. The live attenuated strains in OPV stimulate a strong immune response, which is essential for providing immunity against poliovirus.

Live attenuated vaccines are typically designed to mimic a natural infection, leading to the development of both humoral (antibody-mediated) and cellular immunity. This robust immune response is particularly beneficial in controlling viral diseases like polio.

In comparison to other vaccine types, such as inactivated (which use killed viruses), subunit vaccines (which include only pieces of the virus), or monovalent vaccines (targeting a single strain), the live attenuated approach used in OPV has proven effective in preventing the transmission of poliovirus in populations and leading to the global efforts towards eradication.