AIDS

AIDS
Name	AIDS
Synonyms	Acquired immunodeficiency syndrome
Field	Infectious disease, Immunology
Complications	Opportunistic infections, Kaposi's sarcoma, Wasting syndrome
Duration	Lifelong
Causes	HIV
Risks	Unprotected sex, Blood transfusion, Intravenous drug use
Diagnosis	Blood test
Prevention	Condoms, Pre-exposure prophylaxis, Harm reduction
Treatment	Antiretroviral therapy
Medication	Nucleoside reverse transcriptase inhibitors, Protease inhibitors
Prognosis	With treatment, near-normal Life expectancy
Frequency	~39 million living with HIV (2022)
Deaths	630,000 (2022)

AIDS. Acquired immunodeficiency syndrome is a chronic, potentially life-threatening condition caused by the human immunodeficiency virus. By damaging the Immune system, the virus interferes with the body's ability to fight infection and disease. AIDS represents the most advanced stage of HIV infection, characterized by a severely compromised immune system and the occurrence of specific Opportunistic infections or cancers.

Overview

The syndrome was first recognized by the Centers for Disease Control and Prevention in 1981 among homosexual men in Los Angeles and New York City. The World Health Organization declared it a global pandemic, with the Joint United Nations Programme on HIV/AIDS leading international coordination. The discovery of the causative Retrovirus, HIV, is credited to teams led by Luc Montagnier at the Pasteur Institute and Robert Gallo at the National Institutes of Health. The Red ribbon became an international symbol of solidarity, promoted by groups like the ACT UP coalition.

Causes and transmission

AIDS is caused by infection with HIV-1 or, less commonly, HIV-2. The virus is transmitted through contact with certain body fluids, most frequently during Unprotected sex or through sharing equipment for Intravenous drug use. Other routes include Mother-to-child transmission during Pregnancy, Childbirth, or Breastfeeding, and exposure via contaminated Blood transfusions or Organ transplant procedures, though these are now rare in settings with robust screening like the American Red Cross. The virus cannot be spread through casual contact such as handshakes or sharing Utensils.

Symptoms and stages

Initial infection may cause an Acute HIV infection syndrome with flu-like symptoms. This is followed by a prolonged Clinical latency stage, often with no symptoms. Without treatment, progression to AIDS is marked by a decline in CD4+ T cells below 200 cells per microliter or the appearance of AIDS-defining clinical conditions. These include Opportunistic infections like Pneumocystis pneumonia, Toxoplasmosis, and Cryptococcal meningitis, as well as malignancies such as Kaposi's sarcoma and Lymphoma. Wasting syndrome and HIV encephalopathy are also common complications.

Diagnosis and testing

Diagnosis involves Blood tests that detect antibodies to HIV, Antigens, or viral RNA. Common assays include the ELISA and Western blot tests. Rapid tests are used in field settings by organizations like Doctors Without Borders. Confirmatory testing follows guidelines from the Centers for Disease Control and Prevention. The diagnosis of AIDS specifically relies on CD4 count measurement or documentation of an AIDS-defining illness in a person with HIV.

Treatment and management

The standard treatment is Antiretroviral therapy, typically a combination of drugs from classes like Nucleoside reverse transcriptase inhibitors, Non-nucleoside reverse transcriptase inhibitors, Protease inhibitors, and Integrase inhibitors. Landmark trials like ACTG 076 transformed care. Management also includes Prophylaxis against Opportunistic infections and treatment of co-infections such as Tuberculosis and Hepatitis C. Adherence is critical to prevent Drug resistance, monitored through Viral load testing. The Global Fund to Fight AIDS, Tuberculosis and Malaria supports access to treatment worldwide.

Epidemiology

Since the beginning of the epidemic, an estimated 85.6 million people have been infected with HIV, and about 40.4 million have died from AIDS-related illnesses. The Sub-Saharan Africa region remains the most severely affected, with countries like Eswatini, Lesotho, and South Africa having high prevalence. Key affected populations globally include Men who have sex with men, Sex workers, Transgender people, and people in prisons. The President's Emergency Plan for AIDS Relief has been a major source of funding and program support.

Prevention and control

Effective prevention strategies include the consistent use of Condoms, Pre-exposure prophylaxis with drugs like Truvada, and Post-exposure prophylaxis following potential exposure. Harm reduction programs, such as Needle exchange programs, reduce transmission among People who use drugs. Voluntary medical male circumcision is promoted in high-prevalence regions. Mother-to-child transmission can be drastically reduced with Antiretroviral therapy during Pregnancy. Global initiatives are coordinated by UNAIDS, aiming for targets like the 95-95-95 goals to end the epidemic.

Category:Infectious diseases Category:HIV/AIDS Category:Public health