An HIV vaccine trial in Thailand involving 16,000 volunteers showed potentially promising results as transmission of the virus was cut by a third. Médecins Sans Frontières (MSF) welcomes the initiative as it opens up a new chapter in HIV vaccine research.

"As the first vaccine trial to show any significant efficacy, it gives hope for the development of an effective vaccine in the future," said Paul Cawthorne of the MSF Campaign for Access to Essential Medicines in Bangkok. "We welcome this news, but with cautious optimism, as the potential vaccine today offers only 30 percent protection. Also, there are different strains of the virus and there is no guarantee that the trialed vaccine would work in the same way in the most affected regions of the world, such as sub-Saharan Africa."

The development of a new vaccine should not hide the fact that millions of people already infected with HIV are desperately waiting for treatment. Worldwide, 70 percent of people in urgent need of treatment do not get it. Even should an effective vaccine be developed, this situation will remain.

"The discovery of a vaccine is critically important and we support further research," added Cawthorne. "If a full protective vaccine was developed it would need to be made available to all those at high risk at an affordable level."