HIV infection

Definition

HIV infection is a disease caused by the human immunodeficiency virus (HIV). The condition gradually destroys the immune system, which makes it harder for the body to fight infections.

This article provides a general overview. For more detailed information, see:

• AIDS
• Acute HIV infection
• Asymptomatic HIV infection
• Early symptomatic HIV infection

Alternative Names

Human immunodeficiency virus infection

Causes, incidence, and risk factors

The human immunodeficiency virus (HIV) can be spread by the following:

• Contaminated blood transfusions and blood products
• Intimate sexual contact
• The use of contaminated needles and syringes

The virus may also spread from a mother to her baby, either at birth or through breastfeeding.

People who become infected with HIV may have no symptoms for up to 10 years, but they can still pass the infection to others. After being exposed to the virus, it usually takes about 3 months for the HIV ELISA blood test to change from HIV negative to HIV positive.

HIV has spread throughout the US. The disease is more prevalent in urban areas, especially in inner cities.

Symptoms

Symptoms related to HIV are usually due to an infection in part of the body. Some symptoms related to HIV infection include:

• Diarrhea
• Fatigue
• Fever
• Frequent vaginal yeast infections
• Headache
• Mouth sores, including fungal (candida) infection
• Muscular stiffness or aching
• Rash of various types, including seborrheic dermatitis
• Sore throat
• Swollen lymph glands

Note: At the time of diagnosis with HIV infection, many people may not have experienced any symptoms.

Signs and tests

The HIV ELISA and HIV Western blot tests detect antibodies to the HIV virus in the blood. Having these antibodies means you are infected with HIV.

• If the test is negative (no antibodies found) and you have risk factors for HIV infection, you should be retested in 3 months.
• If the HIV ELISA and HIV Western blot tests are positive, other blood tests can be done to determine how much HIV is in your bloodstream.

White blood cell differential may also show abnormalities.

A lower-than-normal CD4 cell count may be a sign that the virus is suppressing your immune system.