Treatment as prevention: toward an AIDS-free generation

Abstract

In British Columbia, Canada, intensive efforts have been made to implement and maintain a treatment-as-prevention strategy among the HIV-infected population. Acceleration of antiretroviral therapy coverage has resulted in a substantial increase in the median CD4+ cell count at which treatment is initiated and a dramatic decline in community plasma HIV RNA levels. This has resulted in a reduction in diagnoses of new cases of HIV infection, including among injection drug users. Proportions of individuals with viral suppression have steadily increased and the expansion of antiretroviral therapy coverage has not been associated with increased levels of HIV resistance. Further, adoption of routine HIV testing in acute care settings has been very well accepted and has captured new cases at a rate of 5 per 1000 tests outside of high-risk populations, offering an additional strategy for identifying and linking at least some individuals with undiagnosed HIV infection to care. Deriving optimal individual and social health outcomes in HIV infection requires improvement in every element of the cascade of care. This article summarizes a presentation by Julio S. G. Montaner, MD, at the IAS-USA continuing education program held in San Francisco, California, in March 2013.

Figure 1.

Longitudinal community plasma HIV RNA levels and incidence of HIV infection among a cohort of injection drug users in inner city Vancouver, Canada. Adapted from Wood et al.

Figure 2.

Plasma HIV RNA levels over time of all HIV-infected individuals tested in British Columbia, Canada, irrespective of whether they ever received antiretroviral therapy. Adapted with permission from Nosyk et al.

Figure 3.

Changes in incidence of new diagnoses of HIV infection among injection drug users (IDUs) and in non-IDUs in British Columbia, Canada. Adapted from Montaner et al.

Figure 4.

Changes over time in stages in the cascade of care in British Columbia, Canada: diagnosis of HIV infection, linkage to care, retention in care, and proportions of individuals needing and receiving antiretroviral therapy (ART), adhering to ART, and having sustained viral suppression on ART. Adapted with permission from Nosyk et al.,

Figure 5.

Estimate of lives saved by starting antiretroviral therapy at varying CD4+ cell count thresholds in South Africa (top). Costs associated with starting antiretroviral therapy at these thresholds, along with the cumulative cost savings over time (bottom). Adapted from Granich et al.