Trivalent oral polio vaccine contains* type 3 virus -

Ans. is 'c' i.e., 300,000 TC1D 50 Oral (sabin) polio vaccineo It contains live attenuated vimss (type 1, 2 and 3) grown in primary' monkey kidney or human diploid cell culture,o The vaccine containsOver 300.000 TCID 50 of type / poliovirusOver 100,000 TCID 50 of type 2 poliovirusOver 300,000 TCID 50 of type 3 polioviruso Dose - 2 drop (0.1 ml)o Schedule in National Immunization Programme of India.DoseAgeOPV-O (Zero dose)At birthOPV-1OPV-26 weeks10 weeksOPV-314 weeksOPV-B (Booster dose)16-24 monthso Development of immunity - OPV induces local intestinal immunity by production of secretory- IgA as well humoral immunity by inducing production of serum antibodies (IgG). So, it gives protection from paralysis and also prevents infection of the gut by wild viruses.