The world first became aware of AIDS in the early 1980s. Growing numbers of gay men in New York and California were developing rare types of pneumonia and cancer, and a wasting disease was spreading in Uganda. Doctors reported AIDS symptoms under different names, including “gay-related immune deficiency” and “slim,” but by 1985, they reported them all over the world.

From the first days of the AIDS epidemic, the history of HIV has been one of stigma and activism as well as science. The earliest people with AIDS and the health officials advising the public didn’t know what the disease was or how it was transmitted. This uncertainty, and the speed with which the disease spread, led to an “epidemic of fear” and to discrimination against those with HIV and against groups perceived, correctly or not, to be more at risk.

As individuals with AIDS were evicted from housing, barred from attending schools and continuing to die with limited treatment, activists fought for money for AIDS research and an end to discrimination.

We now know that HIV existed long before it was identified as the cause of AIDS in 1984. Blood analysis reveals instances of the virus as early as the 1940s. While researchers aren’t sure exactly when and how HIV developed, the most likely theories posit that HIV-1 – the most common strain of the virus – was transmitted to humans from chimpanzees sometime in the early to mid 20th century.

In 1985, the first blood test for HIV was approved. That same year, the first needle exchange program was started in Amsterdam.

In 1986, AZT, a failed cancer drug, was tested as an HIV treatment for the first time. The trial was so successful that researchers stopped the study, not wanting to withhold medication from the placebo group.

AZT was the only AIDS treatment through much of the 90s. In 1996, doctors started to prescribe combinations of medications, including new protease inhibitors, to control HIV. These “cocktails” were a treatment breakthrough, offering much brighter prospects for people living with HIV and AIDS. But the breakthrough only helped those with access to treatment.

Since the development of combination antiretroviral therapy, HIV/AIDS professionals have focused much of their efforts on expanding access to the medications in that treatment. The expansion has largely required funding: more money for national programs to provide medicine to those who couldn’t otherwise afford it and the formation, in 2001, of the Global Fund to Fight AIDS, Tuberculosis and Malaria.

As researchers continue to develop better treatments and more efficient tests, medical professionals, politicians and activists work towards universal access to the condoms, testing and treatment that saves lives.

In 2006, the number of AIDS-related deaths and new HIV infections fell for the first time since the epidemic began 25 years before. According to the most recent estimates, about 33.3 million people are living with HIV today.