The Centers for Disease Control had this to say released an important "Dear Colleague" letter today:

Scientific advances have shown that antiretroviral therapy (ART) preserves the health of people living with HIV. We also have strong evidence of the prevention effectiveness of ART. When ART results in viral suppression, defined as less than 200 copies/ml or undetectable levels, it prevents sexual HIV transmission. Across three different studies, including thousands of couples and many thousand acts of sex without a condom or pre-exposure prophylaxis (PrEP), no HIV transmissions to an HIV-negative partner were observed when the HIV-positive person was virally suppressed. This means that people who take ART daily as prescribed and achieve and maintain an undetectable viral load have effectively no risk of sexually transmitting the virus to an HIV-negative partner.

This means an HIV+ person who is in treatment—they're take their meds—and has an undetectable viral loads can't infect someone with HIV. The statement goes on to note that we need to get more HIV+ people into treatment:

However, according to a recent Morbidity and Mortality Weekly Report, too many gay and bisexual men living with HIV are not getting the care and treatment they need. Among gay and bisexual men living with diagnosed HIV, 61% have achieved viral suppression, more than in previous years, but well short of where we want to be. More work is needed to close this gap and to address the barriers that make it more difficult for some gay and bisexual men, including African American and Hispanic/Latino men, to get HIV care and treatment.

This is really good news—not that undetectable = uninfectious, something doctors, HIV-prevention groups, and other health orgs have acknowledged for years. But the CDC getting on board/recognizing reality is, as Joe Biden might say, a big fucking deal. The CDC finally recognizing that treatment for HIV+ people is the most effective form of prevention—the most effective way to protect negative people from becoming infected with the virus—should lead to more outreach, more testing, and more funding for programs that make antiretroviral therapies available to more people. (Another thing that might help: universal fucking healthcare.)

Aggressively treating HIV+ people worldwide while making PrEP available to gay and bisexual men—the people at highest risk of exposure/infection—could eradicate HIV in two or three generations.

It is important to note that "uninfectious," in this context, only applies to HIV. Antiretroviral therapy and PrEP offer no protection against other sexually transmitted infections. The best way to protect yourself from syphilis, gonorrhea and chlamydia—and to lower your risk of contracting herpes or HPV—remains what is now the second-best way to protect yourself from HIV: condoms.

More info at