Microsoft Chairman Bill Gates pledged $100 million Monday to fight AIDS in India, a dramatic initiative he said would focus on helping women protect themselves from careless partners.

The $100 million contribution from the Bill & Melinda Gates Foundation is the largest grant the organization has given to a country to fight the deadly virus.

The foundation is funded by the Microsoft founder's personal wealth, which Forbes magazine estimated in September at $43 billion.

"I realized about 10 years ago that my wealth has to go back to society," said Gates, a father of three who says he was influenced by his own parents' practice of regularly donating to charity.

"A fortune, the size of which is hard to imagine, is best not passed on to one's children. It's not constructive for them."

Gates started his four-day trip through India on Monday with a visit to a private hospice in New Delhi -- where he wore a "tika," the deep red Hindu mark, on his forehead.

"It's a very brave thing to speak out and it's a problem that needs a lot of brave people," Gates told Naveen Kumar, an HIV-positive activist who said India's public health facilities had refused to treat him and his wife.

Kumar said his HIV-positive wife was turned away from public hospitals when she was pregnant. Doctors at one government-run hospital suggested she have an abortion.

"The hospital actually asked my wife to leave. They said it was useless to have the baby," he told Gates. Their daughter is healthy and virus-free, he said.

Gates said his initiative would focus on women, because of their vulnerability to the virus and their lack of access to treatment in India.

"In a conservative society, the effort would be to reach out to the women through other women and to ensure that the resources reach the women," Gates said.

He said the Gates Foundation was looking at programs that teach prevention methods that don't require the cooperation of a male partner.

The foundation has invested $100 million in research on microbicides -- gels designed to kill HIV.

Gates, who also met with Prime Minister Atal Bihari Vajpayee, urged Indian leaders and health professionals to look beyond the stigma of AIDS and publicize its danger.

"HIV-AIDS is at a relatively low level in India and experience shows that countries that act at an early stage can prevent the disease from becoming widespread."

Gates set himself up for criticism by citing a recent U.S. government report that predicts the number of people with HIV in India will rise to 20-25 million by 2010. The figure stands at about 4 million now, about .7 percent of the adult population.

India has rejected the report as inaccurate. Health Minister Shatrughan Sinha on Friday accused Gates of "spreading panic" by citing the figures.

The government has not given an alternate projection, but says it does not expect a dramatic increase. India insists its AIDS-prevention programs are paying off and the number of HIV carriers has stabilized over the last three years.

Gates shrugged off the criticism, and noted that Sinha had agreed to chair the board overseeing the Gates grant and that Vajpayee expressed appreciation for the money.

Gates will meet with industry and government officials in New Delhi, Bombay and the southern software hubs of Hyderabad and Bangalore.

He said he worried that India's enormous progress in information technology -- the country has the only Microsoft software development center outside the United States -- would be thwarted by AIDS.