The last polio case was detected in India in 2011. India was certified Polio free on 27 March 2014, but the immunisation program continues in the country as the neighboring country remains polio endemic viz, Pakistan and Afghanistan. OPV has attenuated live virus . IPV has inactivated polio virus particles. the virus particles retain their antigenicity but are actually killed. Therefore , there is no chance of infection (vaccine associated paralytic poliomyelitis) after IPV vaccination.
There is threat of vaccine derived polio from the trivalent OPV vaccine (types 1, 2 and 3) which is caused by Polio virus type 2. Therefore, trivalent OPV is to be replaced by bivalent OPV (types 1 and 3). The switch is being carried out in the following steps.: 1) Taking back all the trivalent OPV from India. Not a single vial should be found in India. 2) Supplying the bivalent OPV after the trivalent…
