A premier German nongovernmental organization (NGO) is endorsing antiretroviral medication as an effective form of HIV prevention, mirroring last year’s Swiss statement on the lowered risk of transmission from positive people on treatment to their negative partners, aidsmap.com reports.

Researchers from the Swiss Federal Commission for HIV/AIDS said that HIV-positive people on meds and with undetectable viral loads for six months and no sexually transmitted infections (STIs) cannot transmit the virus through heterosexual sex.

According to the article, Deutsche AIDS-Hilfe calls transmission in such circumstances “unlikely” and claims that antiretroviral treatment is as effective as condom use in preventing infection in negative partners.

In a position paper, Deutsche AIDS-Hilfe says that sexual HIV transmission is unlikely when the HIV-positive partner’s viral load has been undetectable for at least six months, the person is adhering to antiretroviral therapy and there is no damage to the mucous membranes.

In those circumstances, the NGO says, the risk of transmission is negligible and, when combined with condom use, is close to zero.