The human immunodeficiency virus (HIV) treatment cascade provides a snapshot of the effectiveness of the health care system in diagnosing and treating the estimated 1.2 million persons living with HIV infection in the United States.1 Like many concepts in health care, the cascade developed and evolved over time.
In 2005, my colleagues and I published an estimate of the population effectiveness of HIV care in the United States, which noted that for HIV care to be effective for an infected population, the following “steps in care” needed to occur: persons with HIV infection need to be diagnosed, enter care, receive antiretroviral therapy, and adhere to antiretroviral therapy and visits.2 Based on the published literature at that time, we estimated that 26% of persons in the United States with HIV infection had viral suppression. Simultaneously, the HIV/AIDS Bureau in the Health Resources and Services Administration developed a continuum of engagement in care model that highlighted the fact that engagement in care was not a permanent state for many persons.3 In 2009, Greenberg et al4 published an HIV cascade that estimated that less than 20% of HIV-infected persons had achieved viral suppression in the Washington, DC area. In 2011, Gardner et al5 published their national estimate of the HIV treatment cascade, estimating from a literature review that only 19% of persons living with HIV in the United States had viral suppression. Subsequent work by the Centers for Disease Control and Prevention (CDC)1 estimated that 26% of persons with HIV infection in the United States were virally suppressed in 2009, and their most recent estimate is that 30% were virally suppressed in 2011.