A steadily increasing proportion of Americans living with HIV have a fully suppressed virus. To arrive at this finding, researchers looked at 2009 to 2013 data on 23,000 HIV-positive people receiving medical care.

During this period, the proportion of those in care who had a fully suppressed virus at their last viral load test steadily increased, from 72 to 80 percent. The proportion of those who had complete viral suppression in all tests during the previous year increased from 58 to 68 percent.

“The findings from this analysis offer promising news for our goals of improving the health of those living with HIV and preventing new infections,” says Heather Bradley, PhD, an epidemiologist in the Division of HIV/AIDS Prevention at the Centers for Disease Control and Prevention, who headed up the study. (Having a fully suppressed virus means individuals are much less likely to transmit HIV to others.) “Encouragingly, the largest increases that we observed were seen among populations with the lowest levels of viral suppression in 2009, including young people and non-Hispanic blacks.”