HIV - the Human Immunodeficiency Virus - is a virus that attacks the immune system resulting in a chronic, progressive illness that leaves people vulnerable to opportunistic infections and cancers. When the body can no longer fight infection, the resulting disease is known as AIDS (Acquired Immunodeficiency Syndrome). On average, it takes more than 10 years for the disease to progress from HIV infection to AIDS.
AIDS is a deadly disease that has already killed more than 25 million people worldwide, according to UNAIDS . Currently, there is no safe and effective vaccine against HIV infection, and no cure for AIDS.
In order to infect, the virus must enter a person's bloodstream (HIV cannot survive outside the body). HIV is transmitted from one person to another through: