And so women (along with men) do battle. They look for new compounds that can prevent infection. They examine the effect of HIV drugs on the girl. And they lend their girl to science.
With all of that, the organizers of the 13th Conference on Retroviruses and Opportunistic Infections (CROI), the most important HIV meeting in the U.S. (held this year in Denver in February), put together a session focusing, in part, on the sexual organs and the advancing research in prevention.
No wonder. As usual, it's one thing to have a vagina, but it's another to have power over it.
When Hillier asked women in India whether they prefer a drug they take every day to prevent infection, or one to take at the time of sex, she was surprised at the answer.
"I thought they'd say they'd rather use it only if they needed it. But they said, 'We would rather use it everyday because we don't get to decide when we have sex and would rather be protected just in case,' " Hillier said.
This type of clinical research, then, needs to deal with not just physically stopping HIV in its track, but with the social environment as well. In her work, Hillier, a professor of Obstetrics, Gynecology and Reproductive Services at the University of Pittsburgh, Magee-Women's Hospital, and other researchers attempt to learn what would fit best into the lives of women, not just what works biologically.
"What is the most acceptable to women and their partners?" Hillier asked.
Look at condoms -- they work biologically, but they're not so good socially.
"And yet," said Hillier, "we tell women in high-risk countries to request that their partner use condoms when in fact we know that's simply not possible.
"I think particularly when we talk about ABC -- abstain, be faithful, and use condoms -- it's important to know that most of us, if we went home and said to our main partner, 'I really would like to use a condom tonight,' that [Fitzgerald's] statement would absolutely be seen as true," she continued. "My husband, I know, would be a little surprised," Hillier cracked.
"And so the great proportion of women at risk for HIV aren't able to use ABC," Hillier noted. "I think most of us recognize that female condoms alone -- and male condoms -- aren't going to provide the answer we need."
Again, the biological meets the social. It's known that the chemical environment of a young woman's vagina makes her more at risk for HIV, until around age 21. But there's more going on.
The imbalance, noted Hillier, "has, in part, to do with something I've never understood, especially since I turned 50: that men tend to like younger women.
"There are also certain economic disparities that women face around the world and certainly women are oftentimes coerced or in economically disadvantaged relationships with men who are infected and they have no capacity to protect themselves."
What can be done, therefore, to increase the power of both the woman and the vagina?
Prevention products for women are one of two things: barrier methods or chemical methods.
Barrier methods include such things as female condoms (not to diminish the role of male condoms), diaphragms, and a vaginal ring that might only need to be changed once a month.
Chemical methods include pills and creams. They are either systemic (absorbed by the body, as with oral drugs) or topical (applied to the surface, such as a gel inserted into the vagina).
The research on topical products focuses on microbicides -- "to kill a microbe" (HIV being one). They are also being developed to kill other microbes as well, for the prevention of other sexually transmitted diseases. Microbicides, currently resembling sexual lubricants, are the leading contenders for grrl power. Their potential for invisibility -- for being used behind a man's back, so to speak -- has the promise of true prevention in women's hands.
"The idea is that microbicides reduce trauma to the epithelial surface -- which enhances the protective barrier." (The epithelial layer of cells in the vagina is known to contain cells that HIV likes to attach itself to, making infection easier.) "They may reduce epithelial inflammation by altering the local innate immune response or by preventing acquisition of sexually transmitted diseases." (The presence of other sexually transmitted diseases is known to increase the risk of becoming infected with HIV.) "They maintain the vaginal pH -- we know that lower pH is less conducive to HIV infection." And, they provide lubrication.
"For a long time people said microbicide trials can never be done and that they'll never be done in the developing world, that the populations are too [problematic], and we'll never be able to get women to use the products. I'm happy to say that in 2006 the trials are well underway," she reported.
The women in HPTN 035, of which Hillier is a researcher, have a very high 92% retention rate and 75% report using the gel product that they're assigned with every act of coitus [vaginal intercourse between a man and a woman]. "I think that's pretty remarkable," Hillier said.
"I think it's an incredibly exciting time in HIV prevention in women," Hillier told her audience. "There are new female barriers being developed, both female condoms and diaphragms. Five different microbicides are in studies underway worldwide and will be completed in the next year or so, showing the first evidence of whether or not there's proof of concept for topically applied microbicides. I find the recent PK [pharmacokinetic] data coming out that finds drug levels in the genital compartments for drugs orally administered to be extremely interesting.
"But even if those [microbicides] studies fail to show a benefit, I think it's important to note that these studies have shown something critically important. One is that these studies can be done in high-risk women. Two, that women are willing to participate in these trials. So I think that these studies are going to be incredibly beneficial in paving the way for future studies of more potent anti-HIV microbicides."
For a webcast or podcast of Hillier's presentation, including her slides, visit www.retroconference.org and see the Monday presentation, "HIV Prevention Research: New Advances, Continued Challenges."