Pulse Polio Immunisation Programme (PPIP):

It was conducted in December 1995 for the first time to eradicate polio from India. In this programme, a dose (0.5 mL) of oral polio vaccine (OPV) is given to a child at different ages (1.5, 2.5 and 3.5 months), along with a booster dose given at 1.5 years of age (now up to 5 years of age). The vaccine helps to develop antibodies against the polio virus in the intestine and blood of the child. The days on which PPIP is conducted in the country are fixed and are known as national immunisation days (NIDS).