Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. This article covers the search for a viable vaccine against HIV, the virus that some people believe to cause AIDS. As there is no known cure for AIDS, the search for a vaccine has become part of medical approaches against the disease by those who believe the virus is a cause. It has been known for many years that HIV is an extremely difficult virus to render harmless, and no cure presently exists. Research into a vaccine is one of several strategies to reduce the worldwide harm from HIV, with other approaches based upon antiviral treatments such as highly active antiretroviral therapy (HAART), and social approaches such as safe sex.