India has not had a case of polio in nine months, raising hopes the country is on the verge of defeating the disease, health officials said Monday.
Ridding itself of polio would be a major symbolic milestone for a nation desperate to move past its image as a Third World country and take its place as a major global player.
India remains one of only four countries in the world where polio is still endemic, and the nine months that it has been without a case is the longest since eradication efforts were launched nearly two decades ago.
"We are close to our goal, but are not taking any chances," said Health Minister Ghulam Nabi Azad.
Polio usually infects children under age 5 through contaminated drinking water. The virus attacks the central nervous system, causing paralysis, muscular atrophy, deformation and, in some cases, death.
While polio has been eradicated in Europe, the Americas, much of Asia and Australia, it remains endemic in India, Pakistan, Afghanistan and Nigeria.
The last new case in India was reported in January in West Bengal state and none has been reported in the traditional polio areas of Bihar and Uttar Pradesh states in more than a year, Azad said.
A country is declared polio free when no cases of the disease are reported for three years, according to the World Health Organization.
"This year is extremely crucial for India to capitalize on the remarkable progress made so far and stop polio virus transmission forever," said Nata Menabde, WHO representative in India.
"The present situation is indeed very promising but also extremely challenging," Menabde said in remarks Monday marking World Polio Day.
India's success has followed "persistent efforts over the last few years in the highest-risk areas and in reaching the most vulnerable populations, such as newborns, migrants and mobile populations," Azad said.
The government is aware, however, that a slip could lead to a resurgence of the disease.
Azad said an immunization campaign continues in all high-risk areas and any new case would be declared a public health emergency.
Health officials also remain concerned about the possibility of the virus entering the country from neighboring Pakistan, where a spate of cases have been reported.
Indian health authorities have set up polio immunization booths at the two border crossings with Pakistan and all children who enter by road and train are being given vaccines.
Both Afghanistan and Pakistan continue to have polio outbreaks, said Rod Curtis of UNICEF's India office.
Authorities have also stepped up preventive measures along India's border with Nepal, with vaccines distributed at 81 points along the 1,120-mile (1,800-kilometer) frontier.
A large chunk of the border is shared with the northern Indian states of Uttar Pradesh and Bihar.
Uttar Pradesh has not reported a case since April 2010, while Bihar has not reported any since September 2010.
"There is no room for complacency _ India must continue to immunize its children against polio, until polio follows smallpox as only the second disease to be wiped off the face of the planet," Curtis said.