HIV Vaccine Awareness Day – May 18, 2012
Modeling Potential Impact on HIV Vaccine Awareness Day
by Margaret McGlynn, President and CEO, International AIDS Vaccine Initiative (IAVI) May 18, 2012
USAID Impact Blog [full text]
Throughout my career, I have witnessed the tremendous power of vaccines to prevent sickness and save lives – delivering incredible victories for humanity against diseases such as polio, smallpox and measles. These vaccines would not have been possible without the inspiration, persistence and courage of researchers, volunteers and health workers around the world.
Thanks to a USAID-supported program, Gladys Njeri Macharia is studying how rare individuals might be blocking HIV infection Photo credit: IAVI
And so today, on HIV Vaccine Awareness Day, I join countless others around the world in reflecting on what it would mean to see AIDS consigned to a list of former pandemics. To achieve that goal, it is essential that we enlist the participation of researchers around the world in the design and development of HIV vaccines.
Young researchers such as Gladys Njeri Macharia in Kenya – who has dedicated her career to exploring immune responses to HIV – will play an especially important role in that effort. And one day, critical scientific questions addressed by this research might help lead to an effective vaccine.
New modeling data available today from the International AIDS Vaccine Initiative (IAVI) and the Futures Institute, with support from the U.S. Agency for International Development (USAID), illustrates how a safe, preventive HIV vaccine that is accessible and affordable can help us end the AIDS pandemic. This information is available in a series of publications and an interactive web tool.
The potential impact of a vaccine is striking. Because HIV is so extraordinarily resistant to the immune response, it is highly unlikely that any single vaccine will be able to prevent infection by all variants of the virus. Still, our modeling shows that if an AIDS vaccine that is only 50% effective is introduced in 2020 to 30% of the population in low- and middle-income countries, 5.2 million new HIV infections could be averted over the first decade. Higher efficacy and more coverage would have an even greater impact on the pandemic.
The world must continue to scale up and improve the response to HIV by using powerful prevention tools that are currently at our disposal. These include condoms, treatment and voluntary medical male circumcision. Our new models show that a vaccine can build on these existing tools and take us down the last mile to the end of the AIDS pandemic.
A 50% effective vaccine combined with greater use of current HIV-prevention tools could prevent nearly 20 million new HIV infections by 2030 – 20 million people that would not need to face the physical, emotional and social hardships caused by the disease and could avoid lifelong, daily antiretroviral treatment to stave off AIDS-related illness or death.
This HIV Vaccine Awareness Day, IAVI and our partners remember those we have lost to AIDS, gain inspiration from those living with and combating the disease today, and look forward to building on the incredible momentum of recent discoveries and study results to deliver on the tremendous potential of an AIDS vaccine.
Statement: NIH – HIV Vaccine Awareness Day – May 18, 2012
Statement of Anthony S. Fauci, M.D. Director, National Institute of Allergy and Infectious Diseases National Institutes of Health [full text]
There is a growing consensus that we can significantly curtail the HIV/AIDS pandemic by implementing scientifically proven HIV prevention strategies, such as voluntary medically supervised adult male circumcision, prevention of mother-to-child transmission and treatment as prevention. With 2.7 million new HIV infections in 2010 alone, however, it is likely that controlling and ultimately ending the HIV/AIDS pandemic will require an effective vaccine as well. This past year, there have been a number of encouraging findings on this front.
Last month, a detailed analysis of specimens from the first HIV vaccine clinical trial to show a modest protective effect yielded important clues about how the vaccine might have worked. These clues suggest directions for improving upon the original vaccine regimen to confer a broader, more potent and longer-lasting effect. The original vaccine regimen was tested among 16,000 adult volunteers in Thailand in a trial co-funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of NIH.
Meanwhile, several other NIAID-sponsored HIV vaccine clinical trials are under way. The largest of these is examining whether a prime-boost vaccine regimen can prevent HIV infection or reduce the amount of virus in the blood of those participants who become infected despite vaccination. These trials are possible because of the generous contributions of time and effort by thousands of study participants, community educators, health care workers and scientists. All those involved deserve our gratitude.
Preclinical animal model studies of HIV infection recently have uncovered valuable leads toward designing a preventive HIV vaccine. Scientists have demonstrated that a vaccine can prevent a virulent monkey version of HIV infection and have shown a correlation between this protection and the presence of specific antibodies to the virus.
In basic HIV vaccine research, scientists are discovering and studying HIV neutralizing antibodies that shield cells in the lab against infection with a wide array of HIV strains collected from infected people worldwide. Researchers are analyzing the structure and evolution of these antibodies and the manner in which they bind to HIV, and are using this information to design new molecules to elicit the antibodies through vaccination. In related experiments, injecting these antibodies directly into monkeys has been shown to prevent infection from a monkey version of HIV. Based on these findings, studies to test this concept in people are being planned.
All of these advances reinforce our confidence that one day we will succeed at creating a safe, highly effective vaccine to prevent HIV infection. To contain and ultimately halt the HIV/AIDS pandemic, even the most effective vaccine must be part of a combination of medical and behavioral HIV prevention tools. That is why NIAID continues to support research into promising HIV prevention strategies, such as vaginal and rectal microbicides, pre-exposure prophylaxis (PrEP) and expanded HIV testing with linkage to care. That is also why the public health community will continue to refine and implement scientifically proven HIV prevention measures, including condom use, harm-reduction strategies for injection drug users, and, notably, treatment as prevention: giving antiretroviral therapy to HIV-infected individuals to dramatically reduce their infectiousness while protecting their health
Vaccines historically have been the single most important tool for controlling epidemics. With an ongoing commitment to HIV vaccine research, we have the potential to radically change the trajectory of the HIV/AIDS pandemic.