CROI 2017: Changes In Viral Suppression Over Time Reveal Disparities in HIV Care


Sustained viral suppression over the course of a year may be a better measure than the most recent viral load test result when it comes to understanding access to and engagement in HIV care, according a study by Centers for Disease Control and Prevention (CDC) researchers presented at the 2017 Conference on Retroviruses and Opportunistic Infections this week in Seattle.

The researchers found that overall, 48% of people had viral load below 200 copies/mL on the all tests they received during 2014, while 8% never fell below this level. But there were substantial disparities based on sex, race/ethnicity, and age.

Durable viral suppression among people with HIV in a community is an important public health indicator. People with low viral load are protected from disease progression and those with undetectable levels are essentially unable to transmit the virus to others.

Nicole Crepaz from the CDC and colleagues examined the proportion of people with durable viral suppression, those who never achieved viral suppression, and changes in viral load status over time among participants in the National HIV Surveillance System.

The most common measure of viral suppression used in surveillance studies and research on the HIV continuum of care is a single most recent viral load test being below 200 copies/mL, the researchers noted as background. But this does not capture viral load dynamics over time. While most antiretroviral therapy trials use 50 copies/mL as the cut-off for undetectable viral load -- indicating successful treatment -- epidemiology studies often use the higher cut-off, which suggests that people are in care and on treatment, even if they don't manage to maintain full viral suppression.

This analysis used National HIV Surveillance System data reported by 33 jurisdictions, representing 70% of all people diagnosed with HIV in the U.S. It included adults (age 13 or older) who were diagnosed with HIV by the end of 2013 and still alive at the end of 2014. Results were calculated for all individuals who met these criteria, as well as for the subset of people who had at least two viral load tests in 2014, taken as an indicator of being in HIV care.


o   75% showed viral suppression on both their first and last tests;

o   11% improved, going from unsuppressed to suppressed;

o   4% worsened, going from suppressed to unsuppressed;

o   10% had unsuppressed virus on both their first and last tests;

"Disparities by sex, race/ethnicity, and age indicate [the] need for intensified efforts to reduce viral load and HIV transmission in the US, " the researchers concluded. But Crepaz also pointed out the good news that viral suppression was more likely to improve than to worsen over time.



N Crepaz, T Tang, G Mars, et al. Viral Load Dynamics Among Persons Diagnosed with HIV: United States, 2014. Conference on Retroviruses and Opportunistic Infections. Seattle, February 13-16, 2017. Abstract 31.