1. HIV AIDS Myths and Facts Slideshow Pictures
2. Take the HIV/AIDS Quiz
3. AIDS Retrospective Slideshow Pictures

Medical Author:

Mary D. Nettleman, MD, MS, MACP

Mary D. Nettleman, MD, MS, MACP

Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.

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Medical Author:

Rowena A. Medina, MD

Medical Author:

Eric S. Daar, MD

Eric S. Daar, MD

Dr. Daar received his undergraduate degree from UCLA and medical degree from Georgetown University School of Medicine. He completed an internship and residency in internal medicine at Cedars-Sinai Medical Center and his clinical and research fellowship in infectious diseases at Cedars-Sinai Medical Center and UCLA.

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Medical Editor:

Jay W. Marks, MD

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

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In this Article

• Acquired immunodeficiency syndrome (AIDS) facts
• What does AIDS stand for? What causes AIDS?
• What is the history of AIDS?
• What are symptoms and signs of AIDS?
• What are risk factors for developing AIDS?
• How is AIDS diagnosed?
• What is the treatment for HIV/AIDS?
• What is the treatment for HIV during pregnancy?
• What is the treatment for non-HIV-infected people who are exposed to the genital secretions or blood someone with HIV?
• What are the complications of HIV?
• What is the prognosis for HIV infection?
• Can HIV infection be prevented?
• Is there a vaccine for HIV?
• What research is being done to find a cure for HIV?
• Where can a person find information about clinical trials for HIV and AIDS?
• HIV-AIDS FAQs
• Find a local Infectious Disease Specialist in your town
• Acquired Immunodeficiency Syndrome (AIDS) Index

Careful investigation has helped scientists determine where AIDS came from. Studies have shown that HIV first arose in Africa. It spread from primates to people early in the 20th century, possibly when humans came into contact with infected blood during a chimpanzee hunt. By testing stored blood samples, scientists have found direct evidence of a human being infected as long ago as 1959.

Once introduced into humans, HIV was spread through sexual intercourse from person to person. As infected people moved around, the virus spread from Africa to other areas of the world. In 1981, U.S. physicians noticed that a large number of young men were dying of unusual infections and cancers. Initially, U.S. victims were predominately homosexual men, probably because the virus inadvertently entered this population first in this country and because the virus is transmitted easily during anal intercourse. However, it is important to note that the virus also is efficiently transmitted through heterosexual activity and contact with infected blood or secretions. In Africa, which remains the center of the AIDS pandemic, most cases are heterosexually transmitted. Twenty years ago, the news that Magic Johnson had acquired HIV heterosexually helped the country realize that the infection was not limited to men who had sex with men. Currently in the U.S., approximately 27% of new HIV infections are a result of heterosexual transmission.

In the years since the virus was first identified, HIV has spread to every corner of the globe and is one of the leading causes of infectious death worldwide. Statistics from the World Health Organization show that approximately 2 million people die each year from AIDS, and 250,000 of these are children. Worldwide, half of HIV-infected people are women. Two-thirds of current cases are in sub-Saharan Africa.

In the U.S., more than 1 million people are currently infected with HIV, and approximately 50,000 are newly infected each year. Over the years, more than 600,000 people in the U.S. have died from AIDS, many of them during what should have been their most productive years of life.