IPOL is unlike the inactivated polio vaccine invented by Jonas Salkor the oral polio
vaccine ("OPV"), made from a live attenuated virus, invented by Albert Sabin. As described in
the package insert for IPOL, the “culture technique and improvements in purification,
concentration, and standardization of poliovirus antigen produce a more potent and consistent
immunogenic vaccine than the inactivated poliovirus vaccine (IPV) available in the US prior to
1988. Indeed, while Salk's IPV contained 20, 2 and 4 D antigen units of PV types 1 , 2, and 3 ,
by introducing a new culture technique using cells on microcarrier beads in suspensions cultured
in large stainless steel tanks, IPOL contains 40, 8 and 32 D antigen units of types 1 , 2, and 3.
Meaning, vaccine production methods for IPOL allow for higher concentrations of vaccine
antigens in IPOL than were attainable in previous inactivated polio vaccines.4