Three sub-Saharan African nations hard-hit by HIV have seen significant progress in the effort to provide widespread effective treatment for the virus and slow its spread.

More than half of those living with the virus who are on treatment have a fully suppressed viral load, which means these countries are approaching the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 targets for tackling the epidemic.

In 2014, UNAIDS called upon every nation worldwide to get 90 percent of its HIV population diagnosed, 90 percent of that group on treatment and 90 percent of that group to full viral suppression. This would translate to an overall viral suppression rate of 73 percent among all people living with HIV.

Because transmitting HIV when an individual has a fully suppressed virus is very improbable, if not impossible, reaching such high national levels of viral suppression would likely drive down transmission rates.

Researchers from the Population HIV Impact Assessment (PHIA) Project conducted household surveys of approximately 80,000 adults and children in Zimbabwe, Malawi and Zambia in 2016.

The investigators estimated that less than 1 percent of the national populations contract HIV annually. This compares with transmission rates between 1.3 percent and 1.5 percent per year for those countries according to a 2003 estimate. The 2016 estimate that 10 to 14 percent of adults in each country were living with the virus is comparable to a 2010 estimate.

In Zimbabwe, Malawi and Zambia an estimated 60.4 percent, 67.6 percent and 59.8 percent of those living with HIV are virally suppressed, respectively. In each nation, a respective 86 percent, 91 percent and 89 percent of those on antiretroviral treatment for HIV are virally suppressed.

To read a press release about the study, click here.