Bivalent oral polio vaccine contains which strains of polio virus-

Ans. is 'c' i.e., 1 & 3 * Bivalent oral polio vaccine (BOPV) contains suspension of type 1 and type 3 attenuated Polio viruses (Sabin strains), prepared in primary monkey kidney cell.* Trivalent OPV contains type 1, 2 & 3 attenuated polioviruses. It contains:-i) Over 300,000 TCID 50 of type 1 poliovirusii) Over 100,000 TCID 50 of type 2 poliovirusiii) Over 300,000 TCID 50 of type 3 poliovirus