The U.S. HIV population is spending less time with transmittable virus, as the windows between infection and diagnosis and between diagnosis and viral suppression narrow over time, aidsmap reports. The latter period is shrinking more quickly than the former, with one quarter of those diagnosed in 2016 having lived with untreated virus for an estimated eight years or longer.

Fully suppressing HIV with antiretroviral treatment prevents transmission. So diagnosing people with the virus earlier in the course of their infection and getting them on successful treatment sooner after diagnosis is integral to the effort to reduce the spread of the virus.

Presenting their findings at the 2019 Conference on Retroviruses and Opportunistic Infections (CROI) in Seattle, Centers for Disease Control and Prevention (CDC) researchers analyzed data on the 20,683 to 20,562 new HIV diagnoses reported to the agency annually between 2012 and 2016 by the 27 jurisdictions that provided complete reporting of CD4 and viral load test results.

The study authors used mathematical modeling based on the first post-HIV-diagnosis CD4 test results to estimate the time between infection and diagnosis for the individuals included in the study cohort. A median of an estimated 43 months passed between infection and the cases diagnosed that in 2012. By 2016, this window had narrowed by 9 percent to an estimated 39 months. That year, the 25thto 75thpercentile range of the infection-to-diagnosis window was four to 98 months.

In other words, in 2016, one in four people were diagnosed within an estimated four months of having contracted the virus—that’s the good news. The concerning news is that another one in four people diagnosed that year had been living with undiagnosed virus for an estimated eight years or longer, long enough to put them at a high likelihood of developing advanced HIV disease. 

The infection-to-diagnosis window in 2016 was an estimated 40 months for men and 31 months for women, 45 months for Latinos and 29 months for whites, 58 months for those older than 55 years old and 32 months for those younger than 34 years old, and 63 months for heterosexual males.

Between 2012 and 2016, the median time between HIV diagnosis and viral suppression shrank by 38 percent, from eight months to just five months.

To read the aidsmap article, click here.

To read the conference abstract, click here.

To view a webcast of the conference presentation, click here.