When was HIV (Human Immunodeficiency Virus) discovered and how is it diagnosed?
In 1981, homosexual men with symptoms that now are considered diagnostic of AIDS were first described in Los Angeles and New York. The men had an unusual type of lung infection (pneumonia) called Pneumocystis carinii pneumonia (PCP) and rare skin tumors called Kaposis sarcoma. The patients were noted to have severe suppression of a specific type of immune blood cells, called CD4 cells. These cells, often referred to as T cells, help the body fight infections. Shortly thereafter, this disease was recognized throughout the United States, Western Europe, and Africa. In 1983, researchers in the United States and France described the virus that causes AIDS, now known as HIV. In 1985, a blood test became available that measures antibodies to HIV, which thereby detects the bodys immune response to the HIV. This blood test remains the best method for diagnosing HIV infection. Recently, tests have become available to look for these same antibodies in the saliva and urine. How is HIV spread (tra
