June 5 is an important anniversary in the history of HIV and AIDS in the United States. On this date in 1981 the U.S. Centers for Disease Control and Prevention (CDC) published a Morbidity and Mortality Weekly Report (MMWR), describing cases of a rare lung infection, Pneumocystis carinii pneumonia (PCP), in five young, previously healthy, gay men in Los Angeles. All the men had other unusual infections as well, indicating that their immune systems were not working; two had already died by the time the report is published. This edition of the MMWR marked the first official reporting on what would later become known as AIDS.

The cause of the new, unexplained illness was unknown. But the editorial note that accompanied the MMWR report stated that the case histories suggested a "cellular-immune dysfunction related to a common exposure" and a "disease acquired through sexual contact." Within days after the MMWR was published, additional similar case reports from New York City, San Francisco, and other cities were sent to CDC. Now we know that their disease resulted from infection with HIV and that this was the dawn of the HIV epidemic in the United States.

As we mark this anniversary, we remember the hundreds of thousands of Americans who have lost their lives to HIV disease. We also honor all the men and women who have made important contributions to the fight against HIV and AIDS in the United States and around the globe. And we celebrate the many significant advances in our understanding of the disease and its prevention, diagnosis, and treatment that have been made in the past 37 years. Thanks to diligent efforts of many from across various sectors to implement those advances over the years, today fewer people are being infected with HIV, those diagnosed with HIV are living longer, and fewer people are dying of AIDS.

The progress we've made has been uneven, however, and some people and places are being left behind. But due to the persistence and commitment of many, advances in HIV science, prevention services, and care delivery continue. As a result, today we have the tools that make it possible to end new HIV infections and save lives, if we act now to scale them up and get them to the people who need them.

Although our fight has not yet ended, we have come a very long way since those very early days when so much was unknown about this deadly new disease. As we reflect on how far we have come since this date in 1981, let us each consider what we can do to enhance and focus our efforts to achieve national and global goals to end HIV.

Read more about what happened in the days and weeks following that first report in 1981 and other milestones in the 37-year history of HIV and AIDS in the HIV.gov Timeline of HIV and AIDS.