Gates, whose Bill & Melinda Gates Foundation has committed nearly $1 billion to health and development projects in India, met with health workers and discussed the strategy to fight polio with immunization drives and an effective surveillance program that identifies cases early.
Gates visited Guleria, a village nearly 140 miles east of Patna, the capital of Bihar, one of only two Indian states where new cases of polio continue to be reported, according to UNICEF. Uttar Pradesh is the other.
In 2002, India had reported 1,613 polio cases - a number that has now come down to about 685 cases per year, UNICEF says.
Polio mostly strikes children under 5 and is carried in the feces of the infected and often spread by contaminated water. It usually causes paralysis, muscular atrophy, deformation and sometimes death.
The disease has dropped by more than 99 percent since the World Health Organization and partners launched an initiative to eradicate the disease in 1988 through vaccinations. But the numbers of cases - fewer than 2,000 annually - have remained at a virtual standstill since 2000. In addition to India, polio persists in a handful of countries, including Afghanistan, Angola, Chad, Nigeria, Pakistan and Sudan.
Every year, India mobilizes more than 2 million health workers for an immunization day, visiting more than 200 million homes. To make sure they don't miss anybody, they also go to train stations, bus stations and ferry terminals to immunize children who are on the move.