India and 10 other Asian countries were formally declared polio-free by the World Health Organization (WHO) Thursday.

Apart from India, the other countries which were given polio-free certificates were Bangladesh, Bhutan, North Korea, Indonesia, the  Maldives, Myanmar, Nepal, Sri Lanka, Thailand and Timor-Leste.

The certificates were handed over to the health ministers of these countries by WHO Regional Director (Southeast Asia) Poonam Khetrapal Singh at a ceremony here.

A country is declared polio-free by the WHO, if no case is reported for three consecutive years. India reported the last polio case in January 2011.

An independent panel of 11 experts in public health, epidemiology, virology, clinical medicine and related specialties constituting the Southeast Asia Regional Certification Commission for Polio Eradication met for two days to review evidence from the countries before reaching the decision.

Union Health Minister Ghulam Nabi Azad said: "This (southeast Asia) is the fourth region to be certified polio-free. The distant dream of polio eradication in the region is now a reality."

Azad said that resources were never allowed to be a problem for the campaign against polio. "It was an unbelievable operation. It is a significant step towards global eradication of polio."

He said India embarked on the programme to eradicate polio 19 years ago in 1995, when the disease used to cripple more than 50,000 children in the country every year.

A team of 2.3 million polio volunteers and 150,000 supervisors worked day and night to reach every child, Azad said.

WHO regional director Poonam Khetrapal Singh said: "The goal of polio eradication was made in 1988. It marks one of the biggest public health achievements."

"Let us not forget that the war against polio is not over. There are two regions left where polio still needs to be eradicated," she added.

Khetrapal Singh said the next target was to eradicate measles from the region by 2020, for which the structure put in for polio eradication can be used effectively.