Polio persists in four nations but almost gone in India

(CBS/AP) Poliomyelitis may soon become a thing of the past in India.

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The country hasn't had a case of polio in nine months, raising hopes India is on the verge of defeating the disease, health officials said Monday.

Along with Afghanistan, Nigeria, and Pakistan, India is one of only four countries in the world where polio is still endemic. Ridding itself of polio would be a major milestone for the country desperate to move past its Third World image and take its place as a major global player. Nine months 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 is a virus that usually infects children under age 5 through contaminated drinking water. The virus that causes the disease attacks the central nervous system, resulting in paralysis, muscular atrophy, deformities and, in some cases, death.

When is a country declared polio free? When no cases of the disease are reported for three years, according to the World Health Organization.

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.

But the government is aware that the slightest slip could lead to a resurgence of the disease. An immunization campaign continues in all high-risk areas, and any new case would be declared a public health emergency, Azad said.

In neighboring Pakistan, a flood of polio cases have been reported - so Indian health officials remain concerned about the possibility of the virus entering India. Authorities have set up polio immunization booths at the two border crossings with Pakistan. All children who enter by road and train are being given vaccines. They've also stepped up preventive measures along India's border with Nepal.

"There is no room for complacency," said Rod Curtis of UNICEF's India office. "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.