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Topic Overview
The human immunodeficiency virus (HIV) attacks and gradually weakens your immune system . A weakened immune system makes you more susceptible to opportunistic infections and cancers.
HIV infects CD4+ cells , a type of white blood cell. White blood cells are an important part of the immune system, which helps you fight infections. As HIV-infected CD4+ cells are destroyed or impaired, the immune system becomes less able to fight infection and disease.
See an illustration of how HIV reproduces.
HIV is spread from one person to another through contact with blood, semen, or vaginal fluids. Symptoms of early HIV (acute retroviral syndrome), which are often mistaken for symptoms of another viral infection such as influenza or mononucleosis , include:
- Fever.
- Sore throat.
- Headache.
- Muscle aches and joint pain.
- Enlarged lymph nodes in the neck, armpits, and groin.
- Skin rash.
- Abdominal cramps, nausea, or vomiting.
- Diarrhea.
These early symptoms of HIV usually disappear on their own after 2 to 3 weeks.
Exams and tests play an important role in the diagnosis and treatment of HIV infection. Early diagnosis and an understanding of HIV will help you get the treatment and support you need and improve your chances of staying healthy longer.
Treatment of HIV infection focuses on:
- Slowing the rate at which the virus makes copies of itself (replicates) in your body.
- Preventing or controlling opportunistic diseases .
- Maintaining good overall health by eating well, reducing stress, and staying physically active.
Health professionals and scientists are constantly learning new things about HIV infection and its treatment. By working closely with your health professionals, you will learn:
- When you need to have checkups and blood tests.
- What the latest advances in treating HIV infection and opportunistic diseases are and whether they might be right for you.
- Where you and your family ca
- n get the emotional, social, and financial support you need.
Acquired immunodeficiency syndrome (AIDS)
AIDS is the last of several stages of infection with HIV. AIDS is diagnosed when you:
- Have a CD4+ cell count below 200 cells per microliter (µL) of blood.
- Develop an opportunistic disease or cancer.
More than half of adults with HIV who do not receive treatment develop AIDS within 12 or 13 years. Once the HIV infection progresses to AIDS, death often occurs within 18 to 24 months or sooner in rapid progressors and young children.
Nearly all reported cases of AIDS in the United States can be attributed to:
- Men who have sex with men (homosexual men).
- People who inject illegal drugs (IV drug users).
- People who have multiple heterosexual partners, especially if one or both partners inject illegal drugs.
See additional information about the number of people infected with HIV.
HIV infection in babies and children is more difficult to diagnose than HIV infection in adults.
