AIDS has spread in China primarily through prostitution and intravenous drug use. However, tens of thousands of people, especially in the hard-hit province of Henan, were infected by an unsanitary blood-buying industry in the 1990s.

The proportion of AIDS sufferers who are women jumped from 19.4 percent in 2000 to 27.8 percent last year, Health Minister Gao Qiang said at a Beijing conference about AIDS. "In March this year, the proportion of women rose to 28.1 percent," he said.

Gao blamed the ballooning numbers on a lack of knowledge about the disease, especially among women in poor rural areas. He said fewer than 40 percent of women in the countryside knew how to prevent AIDS.

"Women on the whole know less about the disease than men," Gao said.

Unsanitary Blood-Buying Industry

Health workers are talking to youths and women and distributing posters at schools in the countryside to raise awareness about AIDS prevention, he said.

China says it has 840,000 people who are infected with HIV and 80,000 with full-blown AIDS. But the United Nations' AIDS agency says the true figure is likely higher and that up to 10 million could be infected by 2010 without more aggressive prevention measures.

While the disease has mainly spread in China through prostitution and intravenous drug use, tens of thousands of people, especially in the hard-hit province of Henan, were infected by an unsanitary blood-buying industry in the 1990s.

Dealers bought blood from villagers and pooled it, mixing healthy blood with HIV-infected blood, and often re-used needles.

Sexual Transmission

A 47-year-old female farmer from the central province of Anhui, told the conference she contracted the disease after selling her blood for four years.

"My family was in a difficult situation, so to make money to support my family, I sold blood," Zheng Xiufang said.

Xu Shuqin, an anti-AIDS volunteer from Henan, said she had visited a village where 90 percent of the population had sold their blood and where several had caught AIDS.

Minister Gao said sexual transmission was catching up rapidly as a source of infection for women in China.

More than half of the AIDS patients infected through sexual transmission -- 55 percent -- are now women, Gao said, up from 44 percent in 2001.