Monovalent and trivalent poliovirus vaccines contain live attenuated Sabin strains of poliovirus for administration by the oral route. The term "poliovirus" distinguishes these vaccines from the formaldehyde-inactivated Salk type (Poliomyelitis Vaccine, U.S.P.). Both the live and inactivated vaccines provide protection against paralytic strains of poliovirus by stimulating the production of type-specific serum antibodies. In addition, the live poliovirus vaccine strains induce localized, type-specific intestinal resistance to reinfection with the virus. The relative effectiveness of monovalent live poliovirus vaccine, trivalent live poliovirus vaccine, and inactivated poliomyelitis vaccine has not been established with certainty.
Oral Poliovirus Vaccines. JAMA. 1964;187(13):1015-1016. doi:10.1001/jama.1964.03060260043010