Treatment alone won't stop the AIDS pandemic—as is evident in the fact that for every person who begins HIV treatment, two to three others contract the virus. To prevent and end AIDS, a powerful vaccine is needed.

To mark the National HIV Vaccine Awareness Day, which is May 18, lead researchers at the National Institute of Allergy and Infectious Diseases (NIAID) and at the International AIDS Vaccine Initiative (IAVI) recapped the latest advances and challenges in vaccine research, reiterated their commitment to the cause and thanked those who work and volunteer in the effort.

A clinical trial last year in Thailand showed that a vaccine protected 31 percent of volunteers against HIV infection. “Though this level is modest, it gives us hope that a safe and effective vaccine is possible,” wrote NIAID directors Anthony S. Fauci, MD, Margaret I. Johnston, PhD, and Gary J. Nabel, MD, PhD, in a statement. NIAID is a part of the National Institutes of Health.

Another advancement came last year with the discovery of new antibodies that can neutralize some HIV strains.

Seth Berkley, the CEO and founder of IAVI, noted that considerable work lies ahead and that “making a vaccine against HIV remains one of the toughest problems of modern science.”

The NIAID scientists summed up: “We must remember that a vaccine alone will not end the HIV/AIDS pandemic. If an HIV vaccine is developed, it will need to be used in concert with multiple other scientifically proven HIV prevention tools. NIAID continues to support research into an array of investigational HIV prevention methods, including pre-exposure prophylaxis with antiretroviral drugs, microbicides, and expanded HIV testing and treatment with linkage to care.”