HIV treatment as prevention succeeds by reducing the duration of infectiousness (i.e., time from infection to diagnosis and from diagnosis to viral suppression). HIV testing and linkage to care efforts have been intensified over the years for promoting early HIV diagnosis and early treatment to achieve viral suppression. To evaluate the progress, we examined the time from infection to diagnosis (I-to-D) and from diagnosis to first viral suppression (D-to-VS).
We analyzed data from the National HIV Surveillance System reported through June 2018 from 27 U.S. jurisdictions with complete laboratory reporting. The analyses include persons with HIV infection (PwH) diagnosed at age => 13 years during 2012-2016, whose address at the time of HIV diagnosis was in one of the 27 jurisdictions, and had CD4 and viral load tests after HIV diagnosis. The I-to-D duration was estimated based on the CD4-depletion model. The D-to-VS duration was calculated based on viral load tests. Viral suppression was defined as <200 copies/mL. We censored viral load data at the time of death or by June 30, 2018. The median time and interquartile range for both durations were examined by year when HIV diagnosis occurred, sex, age at HIV diagnosis, race/ethnicity, and transmission category.
Approximately 22,000 PwH per year met the inclusion criteria. The I-to-D duration shortened from 43 months for PwH diagnosed in 2012 to 39 months for PwH diagnosed in 2016 (9.3%). The D-to-VS duration shortened from 8 months for PwH diagnosed in 2012 to 5 months for PwH diagnosed in 2016 (37.5%). Both durations shortened in all sex, age, race/ethnicity, and transmission category. Younger age groups (13-24 and 25-34 years) had shorter I-to-D durations but had longer D-to-VS durations, compared to older groups (35 and older, see Table). Among race/ethnicity groups, Hispanics/Latinos had the longest I-to-D duration (47 months) and blacks had the longest D-to-VS duration (7 months). Among transmission categories, male heterosexuals had the longest I-to-D duration (70 months) and men who have sex with men and inject drugs had the longest D-to-VS duration (8 months).
Our findings show the success of promoting early HIV diagnosis and early treatment as evidenced by the shortened duration of infectiousness over time. Delayed HIV diagnoses continue to be substantial. Targeted and intensified HIV testing and care efforts are needed to address group differences in I-to-D and D-to-VS durations.