January 8, 2013
Lancet reported December 1 results of a Chinese study of serodiscordant couples, with the HIV-positive partner taking antiretroviral drugs immediately upon diagnosis or enrollment in the study ("treated cohort"), or waiting until clinical indicators met guidelines for initiating treatment ("control cohort"), showed "a 26% relative reduction in HIV transmission ... in the treated cohort."
Interpretations of the results differ.
Britain's highly respected AidsMap.com reports the study authors' conclusion, "Our results strongly support the population-wide, real-world feasibility of treating HIV-positive individuals in serodiscordant couples to prevent HIV transmission in a developing country setting."
The United States' equally respected AIDSMeds.com led the story with the headline, "Chinese Study Challenges Treatment as Prevention Strategy," presumably because the reduction in HIV transmission was only 26%.
At issue is how Treatment as Prevention is applied in the field -- in China, or here in the United States. It may not promise to end the epidemic all by itself, but it can help bring a number epidemiologist refer to as "rho" -- the number of future new infections expected to result from each current new infection -- below 1.0. When rho falls below 1.0, the mathematics of the epidemic promise the epidemic will begin to shrink naturally on its own, just as it exploded naturally in the 1980s and early 1990s, when rho may have been as high as 2 or 3. Rho is probably almost exactly 1.0 in the United States today, with the CDC reporting 45-50,000 new infections, year after year.