Could a global program of universal, voluntary, annual HIV testing and immediate treatment for those who test positive effectively extinguish the HIV pandemic? Is such a program feasible? In the June 10 issue of the Journal of the American Medical Association, top HIV/AIDS research leaders at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, set forth a research agenda to answer these and other provocative questions that may help shape the future of HIV prevention.
The inspiration for the research agenda outlined by NIAID director Anthony S. Fauci, MD, and the director of NIAID's Division of AIDS, Carl Dieffenbach, PhD, is a mathematical modeling study published by scientists from the World Health Organization (WHO) in The Lancet in January 2009. The model by Granich et al. predicts that within 10 years of implementation, a program of universal, voluntary, annual HIV testing and immediate treatment for those who test positive could reduce HIV incidence from 20 new cases per 1,000 people per year—the current rate in places like South Africa—to less than 1 case per 1,000 per year. Further, the model predicts that this strategy, colloquially called "test and treat," could end the pandemic within 50 years. Some 33 million people globally are infected with HIV today.
"Given these conclusions, test and treat potentially could represent an important public health strategy for fighting HIV/AIDS," says Fauci. "However, the WHO model is based on numerous assumptions that need to be tested and also raises concerns about individual rights, cost effectiveness and other critical issues that require broad public debate."
To validate these assumptions and address these concerns, Dieffenbach and Fauci articulate a series of areas that define the test and treat research agenda for scientists in the field:
•Feasibility of implementing universal HIV testing
•Relationship of the stage of HIV infection to efficiency of transmission
•Efficacy of antiretroviral therapy in preventing HIV transmission
•Long-term impact of drug resistance
•Behavioral disinhibition (an increase in activities that put an individual at risk for HIV infection)
•Benefit to the individual of early antiretroviral therapy
•Cost-effectiveness of test and treat program for society
Test and treat is one component of a three-part strategy that NIAID is examining to control the HIV/AIDS pandemic. NIAID-sponsored research under way on the second component involves testing whether antiretroviral drugs can prevent HIV infection in people at high risk for acquiring the virus, an approach known as pre-exposure prophylaxis, or PrEP. NIAID also is pursuing research to understand how HIV establishes and maintains latent pockets of infection; this information will be used in future studies to try to develop ways to control and eliminate the cells carrying latent virus, potentially curing people of HIV.
"NIAID is committed to investigating whether these and other experimental approaches to controlling HIV/AIDS work, because together, they have the potential to dramatically curtail the pandemic," says Dieffenbach.
NIAID and its many partners also are conducting research to refine and improve proven HIV prevention strategies such as education and behavior modification of people at risk for contracting or transmitting HIV, practical strategies for reducing HIV transmission among illicit injection drug users, antiretroviral treatment to prevent HIV transmission from mother to child, and medically supervised adult male circumcision. Research on still-experimental approaches to HIV prevention such as topical microbicides and vaccines continues as well.
1. CW Dieffenbach and AS Fauci. Universal voluntary testing and treatment for prevention of HIV transmission. Journal of the American Medical Association DOI: 10.1001/jama.301.22.2380 (2009).
2. RM Granich et al. Universal voluntary HIV testing with immediate antiretroviral therapy as a strategy for elimination of HIV transmission: a mathematical model. The Lancet DOI: 10.1016/S0140-6736(08)61697-9 (2009).