VIENNA, Austria – Of the 39.5 million people around the world living with HIV/AIDS, 67 percent reside in Sub-Saharan Africa. The region has more infections than North America, Europe, the Middle East, Latin America, Asia and the Caribbean combined, according to UNAIDS, the United Nations’ joint program on HIV/AIDS.

Ironically, medical trials now underway in the very region most ravaged by the virus hold the best prospect of finally controlling the disease for which there is no known cure.

In that regard, the advances this and other AIDS-related research being conducted there may change the world’s feelings toward Sub-Saharan Africa from pity to gratitude.

At the 18th biennial International Conference on AIDS held in Vienna last month, scientist were most optimistic about a breakthrough involving microbicide, defined as anything that kills microbes such as bacteria and viruses. The trial is known as CAPRISA 004, after the South African AIDS center which conducted the research.

Using 889 South African women ages 18 to 40, some from Durban and the others from a rural setting about a 90-minute drive from Durban, the study was conducted to determine if a vaginal gel containing the antiretroviral drug tenofovir could be used to prevent HIV infections in women. The clinical study, conducted from May 2007 to December 2009, was supervised by CAPRISA, the Centre for the AIDS Programme of Research in South Africa at the University of KwaZulu-Natal in Durban. It was funded by the United States Agency for International Development (USAID).

Tenofovir is an antiretroviral drug that prevents HIV from replicating inside cells. Half of the study group was given vaginal applicators that contained a 1 percent concentration of tenofovir and the other half was given a placebo that looked identical to the gel. Neither the participants nor the researchers were told which participants were actually given tenofovir. All subjects were told to apply the gel within 12 hours before intercourse and 12 hours after having sex.

The study showed that the women using tenofovir lowered the risk of HIV infection by 39 percent. Those who applied the gel at least 80 percent of the time found it decreased their infection rate by 54 percent. Researchers hope if the dosage is increased, the success rate will be even higher.

Although the study was part of an advanced medical trial, researchers must still validate the results in a larger study before the gel can reach the market. While still not a cure for HIV, the virus that causes AIDS, researchers are delighted at the prospect of developing a product that may give females more control over their bodies, especially women who are vulnerable because they are unable to persuade their husband or mate to use condoms or to be monogamous.

Globally, approximately half of all people living with HIV are women. In Africa, about 60 percent of new HIV infections are acquired by females.

Researchers were elated to experience success after 11 previous microbicide trials failed over the past 15 years.

Phill Wilson, president and CEO of the Black AIDS Institute, the only African-American HIV/AIDS think tank in the United States, said he is proud that the successful study took place in Africa.

“I am busting out all over with pride,” he said. “First, not only was this trial a breakthrough, it was one of the best designed trials I’ve seen and the presentation was just elegant. This was a trial that was conceived, designed, and executed in South Africa by South Africans.”

Wilson said the findings underscore the needs for people of African descent to be involved in medical trials.

Mitchell Warren, executive director of the Vaccine Advocacy Coalition, an international organization based in New York, was particularly impressed by the African women who participated in the study.

“We congratulate the trial sponsors, scientific collaborators, and partners who conducted this trial, and especially want to thank the nearly 900 South African women whose altruism and commitment as trial volunteers made this effort possible,” he said in a statement. “These volunteers and their communities have made an inestimable contribution to HIV prevention research and to the eventual development of new ways for women and men all over the world to protect themselves from HIV. We owe them an enormous debt of gratitude.”

Also underway on the continent of Africa is an early-stage clinical trial that compares the safety and effectiveness of microbicides in women when tenofovir is taken orally in tablet form and when it is applied through a vaginal gel. Known as the VOICE trial or MTN 003, it is the only other microbicide effectiveness study underway.

The findings, based on research now being conducted in four African countries – Malawi, Uganda, Zimbabwe and South Africa – are not expected to be known before 2012.

In addition, studies in Kenya found that male circumcision reduced men’s risk of acquiring HIV through vaginal sex by at least 50 percent, sometimes as much as 60 percent. A report on that study was presented on the last day of the International AIDS Conference.

In 1996, Vancouver was a watershed AIDS convention in which a breakthrough combination therapy of at least three anti-HIV drugs, referred to as Highly Active Antiretroviral Therapy (HAART), was championed. Now, it’s considered a standard treatment cocktail that suppresses the replication of HIV in the blood. Delegates left this year’s conference in Vienna with their eyes fixed on Africa, feeling that the tenofovir gel will do for prevention what HAART did for treatment.

Dr. Halene Gayle, president of CARE, the international anti-poverty organization, said: “The continent that has felt the greatest impact of AIDS may be the continent where we get the greatest answers.”

George E. Curry , former editor-in-chief of Emerge magazine and the NNPA News Service, is a keynote speaker, moderator, and media coach.  You can follow him on Twitter  .