Optimizing the Timing of HIV Screening as Part of Routine Medical Care

Abstract

US federal guidelines recommend that medical providers test all adolescents and adults for HIV infection at least once before the age of 64. The wide age range included in these guidelines may limit their utility and impact. We created an arithmetic model to estimate how HIV screening at different ages would impact the total number of years of undiagnosed HIV infection in the population and the number of persons developing clinical manifestations of HIV/ AIDS. Our base case model assumed that age of infection in the screened population was the same as the estimated age of infection among all persons diagnosed with HIV in the United States in 2010. We parameterized a second model assuming age of infection was similar to the younger age distribution observed in African Americans. In the base case model, the number of years of undiagnosed HIV infection and number of persons with clinical manifestations of HIV/AIDS were both minimized by screening at age 34. If age of infection was similar to that estimated to occur among African Americans, testing at age 24 and 27 would minimize the number of years of undiagnosed infection and clinical cases, respectively. For both parameterization scenarios, testing between the ages of 21 and 38 resulted in outcomes within 10% of the model's estimated optimal age for screening. Focusing HIV screening on a narrower age range than is currently recommended may improve the impact of routine HIV screening efforts.

Agent-based network model predicts strong benefits to youth-centered HIV treatment-as-prevention efforts

“…Our results come with the caveat that the failure to achieve 100% suppression is due primarily to steep drop-offs in steps in the treatment cascade that occur subsequent to testing. Under an alternative framework in which testing (rather than linkage to care) is the limiting factor, others have reported that targeting strategies may be optimally directed at slightly older people as prevalence tends to increase with age (Bershteyn et al 2016, Golden et al 2017. Another caveat is that our model ignores the tendency in many societies for younger women to partner with older men (Barbieri andHertrich 2005, Harling et al 2014).…”

“…Alsallaq et al (2017) note, however, that "youth-focused" prevention and treatment programs can outperform "adult-focused" programs, suggesting a more effective approach for HIV eradication. While age-based HIV testing has been modeled (Bershteyn et al 2016, Golden et al 2017), we are not aware of other models focused specifically on targeting youth for antiretroviral treatment.…”