December 1, 2012 - 11:56 AMT
December 1 marks World AIDS Day

World AIDS Day is held on December 1 each year and is an opportunity for people worldwide to unite in the fight against HIV, show their support for people living with HIV and to commemorate people who have died.

World AIDS Day was the first ever global health day and the first one was held in 1988.

AIDS, or acquired immunodeficiency syndrome, is caused by HIV, or the human immunodeficiency virus, and is considered the last step of the infection.

Globally an estimated 34,4 million people, 1.2 million of them in the U.S., have HIV. More than 25 million people between 1981 and 2007 have died from the virus, making it one of the most destructive pandemics in history.

The 2012 theme for World AIDS Day is "Working Together for an AIDS-Free Generation".