Definitions

AIDS

AIDS

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AIDS or acquired immunodeficiency syndrome, fatal disease caused by a rapidly mutating retrovirus that attacks the immune system and leaves the victim vulnerable to infections, malignancies, and neurological disorders. It was first recognized as a disease in 1981. The virus was isolated in 1983 and was ultimately named the human immunodeficiency virus (HIV). There are two forms of the HIV virus, HIV-1 and HIV-2. The majority of cases worldwide are caused by HIV-1. In 1999 an international team of genetic scientists reported that the strain of HIV-1 responsible for most cases of AIDS can be traced to a closely related strain of virus, called simian immunodeficiency virus (SIV), that infects a subspecies of chimpanzee (Pan troglodytes troglodytes) in W central Africa. Chimpanzees are hunted for meat in this region, and it is believed the virus may have passed from the blood of chimpanzees into humans through superficial wounds, probably in the early 1930s.

Action of the Virus

In a process still imperfectly understood, HIV infects the CD4 cells (also called T4 or T-helper cells) of the body's immune system, cells that are necessary to activate B-lymphocytes and induce the production of antibodies (see immunity). Although the body fights back, producing billions of lymphocytes daily to fight the billions of copies of the virus, the immune system is eventually overwhelmed, and the body is left vulnerable to opportunistic infections and cancers.

Signs and Symptoms

Some people develop flulike symptoms shortly after infection, but many have no symptoms. It may be a few months or many years before serious symptoms develop in adults; symptoms usually develop within the first two years of life in infants infected in the womb or at birth. Before serious symptoms occur, an infected person may experience fever, weight loss, diarrhea, fatigue, skin rashes, shingles (see herpes zoster), thrush, or memory problems. Infants may fail to develop normally.

The definition of AIDS has been refined as more knowledge has become available. In general it refers to that period in the infection when the CD4 count goes below 200 (from a normal count of 1,000) or when the characteristic opportunistic infections and cancers appear. The conditions associated with AIDS include malignancies such as Kaposi's sarcoma, non-Hodgkin's lymphoma, primary lymphoma of the brain, and invasive carcinoma of the cervix. Opportunistic infections characteristic of or more virulent in AIDS include Pneumocystis carinii pneumonia, herpes simplex, cytomegalovirus, and diarrheal diseases caused by cryptosporidium or isospora. In addition, hepatitis C is prevalent in intravenous drug users and hemophiliacs with AIDS, and an estimated 4 to 5 million people who have tuberculosis are coinfected with HIV, each disease hastening the progression of the other. Children may experience more serious forms of common childhood ailments such as tonsillitis and conjunctivitis. These infections conspire to cause a wide range of symptoms (coughing, diarrhea, fever and night sweats, and headaches) and may lead to extreme weight loss, blindness, hallucinations, and dementia before death occurs.

Transmission and Incidence

HIV is not transmitted by casual contact; transmission requires a direct exchange of body fluids, such as blood or blood products, breast milk, semen, or vaginal secretions, most commonly as a result of sexual activity or the sharing of needles among drug users. Such a transmission may also occur from mother to baby during pregnancy or at birth. Saliva, tears, urine, feces, and sweat do not appear to transmit the virus.

By 2007 it was estimated that as many as 33.2 million people were infected with HIV worldwide, the great majority in Third World countries; some 25 million had died from AIDS. The disease in sub-Saharan Africa, which has been especially hard hit, in the main has been transmitted heterosexually and has been exacerbated by civil wars and refugee problems and less restrictive local mores with regard to sex. Some 22.5 million people were infected with HIV in this region, where, in many countries, the prevalence of AIDS has lowered the life expectancy.

In the United States, the demographics of AIDS have changed over time. In the 1980s it was seen mainly in homosexual and bisexual men and was one of the spurs to the gay-rights movement, as activists lobbied for research and treatment monies and began education and prevention programs. Also in the early years, before careful screening of blood products was deemed necessary, the virus was contracted by an estimated 9,000 hemophiliacs (see hemophilia), and a small number of people were infected by surgical or emergency blood transfusions. Before long, however, the majority of new HIV infections were seen in drug users who contracted the disease from shared needles or unprotected sex. A large proportion of infected women are drug users or partners of drug users. Nearly a third of the infants born to HIV-infected women are infected with the virus. (Some of these infants test positive for AIDS only because of the mother's antibodies and later test negative.)

Tests and Treatment

Various blood tests now are used to detect HIV. The most frequently used test for detecting antibodies to HIV-1 is enzyme immunoassay. If it indicates the presence of antibodies, the blood is more definitively tested with the Western blot method. A test that measures directly the viral genes in the blood is helpful in assessing the efficacy of treatments.

There is no cure for AIDS. Drugs such as AZT, ddI, and 3TC, which are reverse transcriptase inhibitors, have proved effective in delaying the onset of symptoms in certain subsets of infected individuals. The addition of a protease inhibitor, such as saquinovir, amprenavir, or atazanavir, to AZT and 3TC has proved very effective, but the drug combination does not eliminate the virus from the body. Efavirenz (Sustiva), another type of reverse transcriptase inhibitor, must be taken with protease inhibitors or older AIDS medicines. Highly active antiretroviral therapy (HAART), a combination typically of three or more anti-AIDS drugs, is now the preferred treatment. Opportunistic infections are treated with various antibiotics and antivirals, and patients with malignancies may undergo chemotherapy. These measures may prolong life or improve the quality of life, but drugs for AIDS treatment may also produce painful or debilitating side effects.

Many experimental AIDS vaccines have been developed and tested, but none has yet proved more than modestly effective, including some that underwent full-scale testing. The development of a successful vaccine against AIDS has been slowed because HIV mutates rapidly, causing it to become unrecognizable to the immune system, and because, unlike most viruses, HIV attacks and destroys essential components of the very immune system a vaccine is designed to stimulate.

Governments and the pharmaceutical industry continue to be under pressure from AIDS activists and the public in general to find a cure for AIDS. Attempts at prevention through teaching "safe sex" (i.e., the relatively safer sex accomplished by the use of condoms), sexual abstinence in high-risk situations, and the dangers to drug users of sharing needles have been impeded by those who feel that such education gives license to promiscuity and immoral behaviors.

Bibliography

See S. Sontag, AIDS and Its Metaphors (1989); S. Flanders, AIDS (1991); G. Corea, The Story of Women and AIDS (1992), publications of Gay Men's Health Crisis, the National Institute of Allergy and Infectious Diseases, and the Centers for Disease Control and Prevention.

in full acquired immunodeficiency syndrome

Transmissible disease of the immune system caused by HIV. AIDS is the last stage of HIV infection, during which time the individual develops frequently fatal infections and cancers, including Pneumocystis carinii pneumonia, cytomegalovirus (CMV), lymphoma, and Kaposi sarcoma. The first AIDS cases were identified in 1981, HIV was isolated in 1983, and blood tests were developed by 1985. According to the UN's 2004 report on AIDS, some 38 million people are living with HIV, approximately 5 million people become infected annually, and about 3 million people die each year from AIDS. Some 20 million people have died of the disease since 1981. Sub-Saharan Africa accounts for some 70 percent of all HIV infections. Rates of infection are lower in other parts of the world, but the epidemic is spreading rapidly in eastern Europe, India, South and Southeast Asia, Latin America, and the Caribbean.

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The Joint United Nations Programme on HIV and AIDS, or UNAIDS, is the main advocate for accelerated, comprehensive and coordinated global action on the HIV epidemic.

UNAIDS' mission is to lead, strengthen and support an expanded response to HIV and AIDS that includes preventing transmission of HIV, providing care and support to those already living with the virus, reducing the vulnerability of individuals and communities to HIV and alleviating the impact of the epidemic.

Five major components make up the role of UNAIDS:

  1. Leadership and advocacy for effective action on the epidemic
  2. Strategic information and technical support to guide efforts against AIDS worldwide
  3. Tracking, monitoring and evaluation of the epidemic and of responses to it
  4. Civil society engagement and the development of strategic partnerships
  5. Mobilization of resources to support an effective response

Headquartered in Geneva, Switzerland, its first and current executive director is Dr. Peter Piot, Under-Secretary General of the United Nations.

UNAIDS Cosponsors

The Cosponsors and the UNAIDS Secretariat comprise the Committee of Cosponsoring Organizations, which meets annually.

Role

The aim of UNAIDS is to help mount and support an expanded response – one that engages the efforts of many sectors and partners from government and civil society.

Established in 1994 by a resolution of the UN Economic and Social Council and launched in January 1996, UNAIDS is guided by a Programme Coordinating Board with representatives of 22 governments from all geographic regions, the UNAIDS Cosponsors, and five representatives of nongovernmental organizations (NGOs), including associations of people living with HIV/AIDS.

Partnerships

The United Nations Declaration Commitment on HIV/AIDS provides the guiding framework for UNAIDS action. Promoting partnerships among various stakeholders is reflected within the leadership section of the Declaration of Commitment. In particular, it calls for complementation of government efforts by the full and active participation of civil society, the business community and the private sector through:

  • Establishing and strengthening mechanisms that involve civil society including faith-based organizations (FBOs), the private sector, and people living with HIV/AIDS at all levels
  • Encouraging and supporting local and national organizations to expand and strengthen regional partnerships, coalitions and networks
  • Full participation of people living with HIV/AIDS (PLWHA), those in vulnerable groups and people mostly at risk, particularly young people
  • Addressing issue of stigma and discrimination.

UNAIDS works to promote partnerships among and between this diverse and broad range of non-state entities. This calls for increases in both the number of new actors, as well as in innovative ways of working, to facilitate increased capacity of non-state entities to respond effectively to the epidemic at all levels.

With the momentum generated by the UN Special Session on HIV/AIDS, the main challenges are to:

  • Sustain and deepen involvement of those contributing and critical to the response such as PLWHA organizations
  • Move beyond the organizations already involved and reach out to optimally engage a broad range of sectors/actors.

From policy to action

In engaging non-state entities in an expanded response to the epidemic, the UNAIDS Secretariat:

  • Fosters and supports global, regional and country level partnerships which include linkages between and among civil society, private sector, philanthropy, media, and with particular attention to organizations of people living with HIV/AIDS
  • Supports governments and UN agencies in developing partnerships with non-state entities. This includes support for approaches intended to increase participation, improve connectedness of efforts and strengthen the various participants' capacity for action.

Donors

As the main advocate for global action on HIV/AIDS, UNAIDS leads, strengthens and supports an expanded response aimed at preventing the transmission of HIV, providing care and support, reducing the vulnerability of individuals and communities to HIV/AIDS, and alleviating the impact of the epidemic. To fulfil this mandate, UNAIDS is supported by voluntary contributions from governments, foundations, corporations, private groups (for example, students, universities, sporting clubs, etc.) and individuals.

In 2003, more than US$118.5 million was received from 30 governments, philanthropic organizations, individuals from around the world and others. The largest donors were the Netherlands followed by Norway, the United States, Sweden, the United Kingdom and Japan. In 2004, 35 governments contributed to UNAIDS.

See also

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