HIV/AIDS

Also called: Acquired immunodeficiency syndrome, AIDS, HIV, Human immunodeficiency virus

MEDICAL ENCYCLOPEDIA

National Institutes of Health

The primary NIH organization for research on HIV/AIDS is theNational Institute of Allergy and Infectious Diseases

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Find health information in languages other than English on HIV/AIDS

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Summary

HIV stands for human immunodeficiency virus. It harms your immune system by destroying the white blood cells that fight infection. This puts you at risk for serious infections and certain cancers. AIDS stands for acquired immunodeficiency syndrome. It is the final stage of infection with HIV. Not everyone with HIV develops AIDS.

HIV most often spreads through unprotected sex with an infected person. It may also spread by sharing drug needles or through contact with the blood of an infected person. Women can give it to their babies during pregnancy or childbirth.

The first signs of HIV infection may be swollen glands and flu-like symptoms. These may come and go within two to four weeks. Severe symptoms may not appear until months or years later.

A blood test can tell if you have HIV infection. Your health care provider can do the test, or you can use a home testing kit. Or to find free testing sites, call the national referral hotline at 1-800-CDC-INFO (1-800-232-4636 in English and en español; 1-888-232-6348 - TTY).

There is no cure, but there are many medicines that fight HIV infection and lower the risk of infecting others. People who get early treatment can live with the disease for a long time.

Strategies to reduce the risk of HIV infection include not having sex, limiting your number of sexual partners, never sharing needles, and using condoms the right way every time you have sex. People who are at high risk may take HIV prevention medicines.

Start Here

HIV / AIDS (National Institute of Allergy and Infectious Diseases)
HIV and AIDS: Know the Facts (National Institutes of Health)Also in Spanish
HIV/AIDS (Mayo Foundation for Medical Education and Research)
HIV/AIDS Basics (Centers for Disease Control and Prevention)
What Is HIV/AIDS? (AIDS.gov)

Symptoms

HIV/AIDS - Signs & Symptoms (Healthy Roads Media)
Signs and Symptoms (AIDS.gov)

Diagnosis and Tests

CD4 Lymphocyte Count (National Library of Medicine)Also in Spanish
Get Tested for HIV (Office of Disease Prevention and Health Promotion)
HIV Screening Test (National Library of Medicine)Also in Spanish
HIV Testing (Centers for Disease Control and Prevention)Also in Spanish
HIV Viral Load (National Library of Medicine)Also in Spanish
HIV/AIDS - Testing (Healthy Roads Media)
Information Regarding the OraQuick In-Home HIV Test (Food and Drug Administration)
Screening for Human Immunodeficiency Virus (HIV) (U.S. Preventive Services Task Force) - PDF
Testing for HIV (Food and Drug Administration)

Prevention and Risk Factors

CDC Vital Signs: HIV and Injection Drug Use (Centers for Disease Control and Prevention)Also in Spanish
HIV Risk and Prevention (Centers for Disease Control and Prevention)Also in Spanish
HIV Transmission (Centers for Disease Control and Prevention)Also in Spanish
HIV Transmission Risk (Centers for Disease Control and Prevention)
HIV/AIDS - Prevention (Healthy Roads Media)
HIV/AIDS - Reducing Your Sexual Risk (Healthy Roads Media)
How Is HIV Transmitted? (AIDS.gov)
Post-Exposure Prophylaxis (AIDS.gov)
Post-Exposure Prophylaxis (PEP) (AIDSinfo)Also in Spanish
Pre-Exposure Prophylaxis (PrEP) (AIDS.gov)
PrEP (Pre-Exposure Prophylaxis) 101 (Centers for Disease Control and Prevention)Also in Spanish
What is a Preventive HIV Vaccine? (AIDSinfo)Also in Spanish

Treatments and Therapies

HIV/AIDS Medicines: MedlinePlus Health Topic (National Library of Medicine)Also in Spanish

Living With

HIV Genotypic Resistance Testing (American Association for Clinical Chemistry)
HIV Resistance Testing (New Mexico AIDS Education and Training Center)Also in Spanish
Live Well (Centers for Disease Control and Prevention)