For more than two years, the women of Darfur in western Sudan have been raped and murdered in attacks by government-supported militias known as "Janjaweed", despite international condemnation of what the United States calls genocide.
Sarah Martin is an advocate with the group Refugees International, in Washington D.C., who has just returned from Darfur.
"We've heard cases where women have gone in to report a rape and have been harassed, have been arrested for adultery. And on top of that, it's even more difficult because in order to get medical treatment for a rape, a woman has to fill out a police report and the police are turning them away from the clinics," she said.
Ms. Martin says the plight of rape victims is especially dire in Darfur because roughly nine out of ten Sudanese women undergo an extreme form of female circumcision.
"All of their external genitalia have been removed and they are sewn up. So this means the consequences of the rape are incredibly traumatic to the women's bodies. This is particularly why it's so vital that they receive medical care after the rape, because often they're bleeding, they're injured, and without treatment, they can get infected and die."
Ms. Martin says, even if women survive the rape, they may still contract the HIV virus. She says there are no accurate statistics on AIDS transmission in Sudan, but men refuse to get tested for the virus, and women are afraid to admit they have been raped.
It's a common pattern. Worldwide, the growth of HIV/AIDS infection has alarmed international health agencies, which say almost half of all adults infected with HIV are now women. In hard-hit sub-Saharan Africa, 57 percent of those with the virus are women.
Janet Walsh, of Human Rights Watch in New York, says the rising number of women infected with HIV is directly related to systemic abuses of women's rights.
"There's something going on here and it has to do with gender. And what we think it is, is a whole series of violations of women's rights that contribute to their vulnerability to being infected with HIV and that also interfere with their access to information and treatment," says Ms. Walsh.
"Women are biologically more vulnerable to becoming infected with HIV than men are," says
Jennifer Kates, the head of HIV policy at the health research group, Kaiser Family Foundation, in Washington D.C.
"In addition to that biological vulnerability, women face a range of other challenges,” she continued, “discrimination, stigma, lack of access to information and education, lack of access to rights and property rights and ownership rights. All of those things combine to make women more vulnerable, and particularly young women."
Young women in developing countries are also more vulnerable to human trafficking syndicates who exploit the women's desire to seek better economic opportunities. The U.S. State Department says of the estimated 600,000 to 800,000 people trafficked across international borders each year, some 80 percent are women and girls. And women trafficked for prostitution have a high rate of HIV infection.
Since the 1990s, rising unemployment in Eastern Europe and greater freedom of movement has fueled a boom in human trafficking.
In Russia, labor groups estimate one fifth of the five million illegal immigrants are victims of forced labor.
Widespread sex tourism in Thailand has made the country a source, transit, and destination country for women and girls trafficked for sexual exploitation.
Wenchi Yu Perkins runs the anti-trafficking program at Vital Voices, a women's rights group in Washington D.C. She says most trafficking victims believe they will find a legitimate job in another country, but end up trapped in slave-like conditions.
"Most of them choose to go overseas,” says Ms. Perkins. “However, they do not realize that once they arrive in the destination countries, their passports are taken away, they're forced into prostitution or all kinds of other types of work."
Health experts and women's rights activists say governments must do more. They are calling for more AIDS prevention and treatment programs specifically aimed at women. And they warn that over the long term, the global AIDS crisis will worsen unless governments eliminate women's rights abuses that persist around the world.