Scientists attending the 21st International AIDS Conference in Durban say there is still no vaccine in sight to prevent HIV/AIDS infections.
While it is impossible to predict when such a goal will be reached, says Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, he is optimistic about researchers' progress.
"It is impossible to say exactly how far we are, but one thing we can say is that over the last seven years we have made important strides in the direction of getting a vaccine,” he said, “but getting an HIV vaccine will probably be one of the most important and difficult scientific challenges in all of HIV research."
Although no specific vaccine has become the sole hope, scientists are vigorously pursuing tests and trials called HVTN 702. The vaccine being tested was developed from a trial in Thailand several years ago, and showed a modest degree of effectiveness.
The trial of the vaccine is set to start in South Africa and other African countries later this year, but Fauci says it could be quite some time before results are known.
"It will take at least a couple of years to determine if that vaccine works,” he said. “If it does, then hopefully we will be closer to where we need to be."
The Vaccine Research Center at the Chris Hani Baragwanath Hospital in South Africa is testing the ALVAC gp120 vaccine, according to Fatima Laher, who leads the center.
"The vaccine work that we do is to prevent HIV infection from happening in people who are negative,” she said. “We are only a few months away from opening that trial that will show whether or not this vaccine will prevent people from getting HIV."