Explanation:

India has made polio vaccination mandatory for people going to or coming from seven polio-endemic countries in a bid to stop the disease from re-entering the country. India will officially be declared polio-free on Tuesday by the WHO after three consecutive years of no new polio cases.
People going to or coming from Afghanistan, Nigeria, Pakistan, Ethiopia, Kenya, Somalia and Syria will have to get polio vaccination certificates. The travel requirement will come into force from March 1 and will require travelers to take polio drops at least a month before arrival or departure from India. The certificate will be valid for one year.