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HIV/AIDS

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The human immunodeficiency virus (HIV) is a retrovirus that infects cells of the human immune system, destroying or impairing their function. In the early stages of infection, the person has no symptoms. However, as the infection progresses, the immune system becomes weaker, and the person becomes more susceptible to so-called opportunistic infections.

The most advanced stage of HIV infection is acquired immunodeficiency syndrome (AIDS). It can take 10-15 years for an HIV-infected person to develop AIDS; antiretroviral drugs can slow down the process even further.

HIV is transmitted through unprotected sexual intercourse (anal or vaginal), transfusion of contaminated blood, sharing of contaminated needles, and between a mother and her infant during pregnancy, childbirth and breastfeeding.

More about HIV/AIDS

GENERAL INFORMATION

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MULTIMEDIA

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RELATED TOPICS

- Immunization and HIV/AIDS
- Infant feeding and HIV
- Nutrition and HIV/AIDS
- Oral health and HIV/AIDS
- Reproductive Health Library: HIV/AIDS
- Sexually transmitted infections
- Sexual and reproductive health and HIV
- Tuberculosis and HIV/AIDS

TECHNICAL INFORMATION

Universal Access by 2010
The concept and a framework for universal access to HIV/AIDS prevention, treatment and care.

HIV testing and counselling

- More HIV topics

PUBLICATIONS

Priority interventions: HIV/AIDS prevention, treatment and care in the health sector

Towards universal access: scaling up priority HIV/AIDS interventions in the health sector. Progress report 2008

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STATISTICS

HIV/AIDS country information

UNAIDS/WHO Global HIV/AIDS Online Database



WHO PROGRAMMES AND ACTIVITIES

HIV/AIDS Department

PARTNERS

UNAIDS
The Global Fund

HIV/AIDS IN WHO REGIONS

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Region of the Americas
South-East Asia Region
European Region
Eastern Mediterranean Region
Western Pacific Region


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