[Human immunodeficiency virus type 1 (HIV) and laboratory tests for detection of HIV infection].

Human immunodeficiency virus type 1 (HIV) has been identified as the primary cause of the acquired immunodeficiency syndrome (AIDS). HIV-1 is a prototypical member of the laentivirinae subfamily of human retroviruses. The infections with HIV are notable for involvement of the nervous system, long periods of clinical latency and weak humoral immune responses complicated by persistent viraemia. HIV is spread by sexual contact, exposure to infected blood or blood products, and perinatal transmission from mother to child. The most important feature of HIV is a remarkable complexity of its viral genome. Besides T cells and monocytes, HIV may also infect other types of cells, including glial cells, gut epithelium, and bone marrow progenitors. It has become increasingly important to have sensitive and specific methods to establish the presence of absence of HIV infection. The diagnosis of HIV infection depends on detection of specific antibodies to HIV, detection of circulating viral antigens, isolation of the virus from clinical specimens of detection of genetic material in infected cells and plasma. The most widely used are ELISA as a screening test and Western blot as a confirmatory test.