Every child receives a dose of Oral Polio Vaccine (OPV), a live, attenuated virus which colonises the gastrointestinal tract. This virus competitively inhibits the wild, disease-causing poliovirus. Not only does this prevent pernicious infection in the host, it precludes transmission of the wild poliovirus to other hosts. Since poliovirus cannot survive outside a host for more than two weeks, theoretically it would be eradicated, resulting in the eradication of poliomyelitis.

The campaign proved to be successful, and the incidence of poliomyelitis in India has decreased dramatically: India recorded 4,791 cases of polio in 1994; 2,489 in 1997; 1,600 in 2002; 225 in 2003; and 135 in 2004. Nevertheless, critics charge that the campaign has seriously encroached on other essential public health services at times when health care resources were minimal.
 

if your baby has received the routine vaccination why give pulse polio! Even though your child is vaccinated and has his personal protection, he can still harbour the disease causing virus which is called the Wild virus in the intestines. This Wild virus keeps getting excreted in the stools and is a risk for polio to the unvaccinated children in the community. This Wild virus cannot survive in the atmosphere for long. When the oral polio virus is given it does not allow the Wild virus to live in the intestines and expels them out. It has been observed that Wild virus only lives in the intestines of babies below 5 years of age. So it seems logical that if all babies below 5 yrs of age are given oral polio vaccine simultaneously it helps to eradicate the wild polio virus as I have already said that the wild virus cannot survive in atmosphere. Regarding safety of oral vaccine - it is quite safe and the risk of having problems as compared to injectable is negligible. This programme of pulse polio is being run all over the country to eradicate polio from the country. Similar practice has been able to eradicate polio from many other countries in the world. By not giving pulse polio to your otherwise vaccinated child we are being selfish, doing a disservice to our country and not helping to eradicate polio from the country.