HIV

Human immunodeficiency virus (HIV) is a lentivirus (a member of the retrovirus family) that causes acquired immunodeficiency syndrome (AIDS), a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive.

HIV infects vital cells in the human immune system such as helper T cells (specifically CD4+ T cells), macrophages, and dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: First, direct viral killing of infected cells; second, increased rates of apoptosis in infected cells; and third, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytes that recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunity is lost, and the body becomes progressively more susceptible to opportunistic infections.

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Other articles related to "hiv":

HIV/AIDS In China
... current spread of the human immunodeficiency virus (HIV) in the People's Republic of China (PRC) has been through intravenous drug use and prostitution ... In China, the number of people affected by HIV has been estimated at between 430,000 and 1.5 million, with some estimates going much higher ... hundreds of thousands up to millions of farmers and peasants were infected with HIV through participation in state-run blood collection programs in which contaminated equipment was reused ...
HIV/AIDS In China - History - Recent History - New Legislation
... of China officially announced the first legislation directly aimed at controlling HIV/AIDS the AIDS Prevention and Control Regulations ... These regulations, together with the Five-Year Action Plan to Control HIV/AIDS (2006–2010), are an important step in the development of government policy related to the care and prevention of HIV/AIDS ... bold, these regulations were passed more than 20 years after the first case of HIV infection was identified, which was recently proven ...
HIV/AIDS In Europe
... sharply, as new AIDS therapies have proven to be an effective means of suppressing HIV ... In this area, the routes of transmission of HIV are diverse, including paid sex, sex between men, intravenous drugs, mother to child transmission and heterosexual sex ... However, many new infections in this region occur through contact with HIV-infected individuals from other regions ...
HIV/AIDS In China - History - Early Control Strategies
... Initially, the Chinese government focused its preventive strategies on stopping HIV from entering the country ... stay 1 year or more and Chinese residents returning from overseas to have an HIV test ... and prostitution were strengthened and authorities were allowed to isolate HIV-positive individuals ...
HIV - History - Origins
... Both HIV-1 and HIV-2 are believed to have originated in non-human primates in West-central Africa and were transferred to humans (a process known as zoonosis) in ... HIV-1 appears to have originated in southern Cameroon through the evolution of SIV(cpz), a simian immunodeficiency virus (SIV) that infects wild chimpanzees (HIV-1 descends from the SIVcpz endemic ... The closest relative of HIV-2 is SIV(smm), a virus of the sooty mangabey (Cercocebus atys atys), an Old World monkey living in litoral West Africa (from southern Senegal to western Côte d'Ivoire) ...