HIV, the virus that causes AIDS, has been intensively studied since it discovery in the early 1980s. Despite major advances in understanding and treating this infection, the worldwide HIV pandemic is not over.
Looking back, there has been so much progress in the intervening 35-plus years. Thanks to successful research, our blood supply is now safe, and those who have access to health care can keep their HIV infection under control with anti-HIV drugs. These drugs are more effective, and easier to use, than they were even 10 years ago. But they still must be taken every day, because they do not cure people. People are still at risk of becoming infected, and over 200,000 babies are infected each year when their mothers are not treated prior to birth. Some of these infections will be prevented by better access to drugs, especially in resource-poor areas.
Looking forward, what we really need to stop HIV is an effective vaccine to prevent infection in the first place. Why don’t we have one yet, when we have such effective vaccines for other diseases like polio? The reasons are mostly due to HIV itself, which has a number of properties that allow it to avoid being caught by the immune response. This explains why the first, relatively simple, ideas failed when they were tested in clinical trials. So we know it will not be easy. From many studies in nonhuman primate models, the evidence points to a need to generate high power immunity against parts of HIV that are the same worldwide. The vaccine will also need to have two activities — to both block virus entry and also to kill any virus that slips by the entry blockade.
The good news is that there are several areas of research that are showing promise for success. We have learned that HIV does have an Achilles’ heel, and therefore we know precisely where on the virus to direct vaccine responses to block entry. Several research groups, including ours, have made progress in developing vaccines that can make strong antibody responses, but they do not yet focus on the Achilles’ heel. Here at OHSU, scientists developed a vaccine that generates amazingly potent HIV “killing” immunity in nonhuman primate models. These results are so promising that the human version of the vaccine is going into the clinic for testing soon.
In the coming decade, we should get some encouraging results from clinical vaccine trials that are just starting in Africa and in the U.S. In the meantime, people here in Oregon and Washington continue to be at risk for infection. We have learned that knowledge is power, and if you know your HIV status, you can have better health and prevent transmission to others. That is why it is so important to know your status. Working together, we can make HIV history for future generations.
Nancy L. Haigwood, Ph.D., is a professor of pathobiology & immunology and director at the Oregon National Primate Research Center, OHSU.