July 19, 2010 -- New HIV diagnoses dropped by more than half since the introduction of highly active antiretroviral therapy (HAART) for HIV-infected patients, a Canadian study shows, suggesting that the treatment was effective at reducing viral load.
The study, based on HIV infections treated in the Canadian province of British Columbia -- showed that from 1996 to 2009, for every 100 patients placed on HAART, new HIV diagnoses decreased by 3%. Specifically, the researchers found that:
- HAART use increased overall by 547% between 1996 and 2009;
- During this period, new HIV diagnoses fell overall by 52%;
- Also during this period, rates of sexually transmitted infections (such as chlamydia, gonorrhea, and syphilis) increased, suggesting that the decrease seen in new HIV diagnoses was not related to a decrease in risky sexual behavior.
The study was led by Julio Montaner, MD, director of the British Columbia Centre for Excellence in HIV/AIDS in Vancouver. The results will be presented this week at the International AIDS Society conference in Vienna, Austria, and were published on The Lancet’s web site.
“Our results show a strong and significant association between increased HAART coverage, reduced community viral load, and decreased number of new HIV diagnoses per year in the population of a Canadian province,” the authors say.
HAART Lowers HIV Viral Load
In 2008, there were 33.4 million people living with HIV, 2 million AIDS-related deaths, and 2.7 million new HIV infections worldwide. Montaner and his colleagues note that these numbers triggered “an urgent redoubling of efforts” by the United Nations Joint Programme on HIV/AIDS.
HAART works by stopping the AIDS virus from replicating, which then helps reduce “viral load,” or the levels of the AIDS virus in the blood. This gives the patient’s immune system a chance to regain its strength, which then helps the patient go into remission from the disease. HAART does not eradicate the virus from the body, but it can reduce its presence to a point where the patient can enjoy overall decent health.
The authors said their findings support HAART as a potent component of HIV/AIDS prevention and could be a part of the global efforts to curb the HIV pandemic, which has struck particularly hard in sub-Saharan Africa and Southeast Asia.
Success With HAART
In an accompanying editorial, Franco Maggiolo and Sebastiano Leone of the Division of Infectious Diseases, Ospedali Riuniti in Bergamo, Italy, suggest that HAART must be combined with education and other interventions, such as screening, to reduce HIV/AIDS.
“HAART might prove effective within other risk populations provided that the source individuals are thoroughly identified and correctly treated,” they write. “Therefore we must couple the use of antiretrovirals with risk reduction strategies, and identify infected individuals through information or education interventions that favor individual access to screening programs. Integrated experiences that provide voluntary routine HIV testing and rapid entry into care, such as those recently implemented in Washington, D.C., would tell us whether HAART can succeed as an epidemic control measure.”
Maggiolo and Sebastiano conclude: “While waiting for an effective vaccine, experiences such as those reported today should be strongly considered by clinicians, national and international agencies, policy makers, and all parties involved in the development of treatment guidelines, because the population-based dimension of HAART might play an important part in the future control of the HIV epidemic.”