Undetectable means untransmittable for HIV because of ART, NIH says

Jan. 11 (UPI) -- Suppressing HIV loads to undetectable levels can make the virus untransmittable, a new study says.

No HIV transmission occurred between male gay couples who took antiretroviral therapy, or ART, when one partner was infected with the virus, according to a study published Thursday in JAMA.

This latest study builds on previous research in 2011 that showed when an HIV-positive person in a heterosexual couple adhered to ART early after their diagnosis, that person could not transmit the virus to their partner.

That earlier study showed "a 96.4 percent reduction in HIV transmission." The study did find, however, that participants transmitted HIV to one another when their viral load wasn't fully suppressed, because they didn't begin antiretroviral therapy soon enough or the treatment just wasn't working, the NIH says.

Created in 1996, ART is a combination of drugs that do not kill or cure the virus, rather they help slow down the growth of the virus.

About 1.1 million people in the United States has HIV. Nearly 39,000 people were diagnosed with HIV in the US in 2017, according to the CDC.

Worldwide, nearly 40 million people have been diagnosed with the disease. Close to 22 million of those people, however, were taking an ART regime to reduce their HIV viral loads.

After peaking in 2004, AIDS-related deaths have fallen by 51 percent, due in part to therapies like ART.

Various factors, like access to health care, can make accessing or sticking to an ART regime difficult.

Still, researchers say that having the information on ART's effectiveness can help curb the spread of HIV even more.

"For nearly two decades, scientists have recognized that viral load is a key determinant of HIV transmission. Studies conducted before the availability of antiretroviral therapy revealed that higher viral loads correlate with higher rates of both sexual and perinatal transmission of HIV. Epidemiological studies showed that as the number of people in a community who are virally suppressed rises, the number of new HIV infections falls," the NIH said.