VANCOUVER, Canada — A new emphasis on methods for preventing the spread of AIDS through sexual contact and a major new clinical trial of techniques to stop its transmission from mothers to children were announced here Tuesday as the 11th International Conference on AIDS focused on women's health concerns.
Although the HIV infection rate for women in the United States is growing alarmingly, the number of women infected with the virus that causes AIDS is still low, and the rate among some groups, such as pregnant women, is stabilizing. But around the world, 42% of AIDS victims are female, and experts predict that by the end of the century, most new infections will be in women.
In a speech to the 15,000 delegates, U.S. Secretary of Health and Human Services Donna Shalala announced that the National Institutes of Health will increase funding for research on vaginal gels, foams and creams to help women protect themselves from HIV. Those funds will triple this year to $25 million and will total $100 million over the next four years.
Later, Dr. Peter Piot, head of the United Nations' anti-AIDS program, announced a major clinical trial of an inexpensive new technique for preventing HIV transmission during childbirth. It will involve the drug AZT and be conducted among 1,900 HIV-positive women in Tanzania, South Africa and Uganda.
Although AIDS researchers in the past have been accused of neglecting the concerns of women, the researchers say they are increasingly addressing those needs.
"We have really made incredible advances," said Dr. Yvonne Bryson of the UCLA Children's Hospital. "I am optimistic about our ability to prevent perinatal transmission and create a new generation of children born without HIV."
An estimated 40,000 Americans are infected with HIV each year, about 19% of them women. In 1985, by contrast, the figure for women was 7%. The problem is particularly severe among minority women. An African American or Hispanic woman is 17 times as likely to be infected as an Anglo woman, according to Dr. John Ward of the Centers for Disease Control.
There is some promise for pregnant women, Dr. Susan Davis of the CDC told the meeting. Overall, fewer than two of every 1,000 pregnant women in the U.S. are HIV-positive--for a total of 6,230 women in 1994--and that rate has held steady for several years. Davis said the rate is dropping in the Northeast, the region with the highest rate of infection.
In that region, the infection rate for pregnant women was 4.1 per 1,000 in 1989, but it dropped to 3.2 per 1,000 in 1994, Davis reported. She attributed the decline to better prevention programs for women.
In the developing world, however, prevention programs for women have largely been failures. According to Dr. Christopher Elias, who works in Bangkok, Thailand, for the Population Council, women in developing countries have less premarital or extramarital sex than women in the industrialized world. But many men in those places frequent prostitutes, a population in which HIV infection is endemic.
When the men return home, their "women often have too little power within their sexual relationships to insist on condom use and too little power . . . to abandon partnerships that put them at risk," Elias said. AIDS is the leading cause of death among women ages 25 to 44 in Africa.
Studies sponsored by the National Institutes of Health of the spermicide nonoxynol-9, which kills the AIDS virus, are already underway in Cameroon, and the United Nations is beginning a larger study of nonoxynol-9 in Ivory Coast, South Africa and Thailand.
Transmission of the virus from mother to child is also a major problem in Africa, where as many as 40% of babies born to HIV-positive women are infected. In the United States, such transmission occurred in about 25% of births until 1994, when physicians began treating HIV-positive pregnant women aggressively with AZT. That pushed the rate down to about 8%.
In the new trial announced by Piot, women and infants will receive a short course of therapy--two weeks before birth and two weeks after, or one week after birth or during birth only.