evidence: The cause of Kaposi sarcoma is infection with the virus human herpes virus 8, also called HHV-8. In healthy people, this infection usually causes no symptoms because the immune system keeps it under control. In someone with a weakened immune system, however, HHV-8 can lead to Kaposi sarcoma. [...] - AIDS-related or epidemic Kaposi sarcoma. This type happens in people infected with human immunodeficiency virus, also called HIV. HIV is the virus that causes AIDS. [...] Thanks to better antiviral medicines to treat AIDS and ways to prevent it, Kaposi sarcoma has become less common and less severe in people with AIDS. Taking antiviral medicines can lower the amount of the virus that causes HIV/AIDS and make the immune system stronger. This might be the only treatment needed for Kaposi sarcoma.