HIV & AIDS Health Center

Why It Is Done

A test for the human immunodeficiency virus (HIV) is done to:

• Detect an HIV infection. Testing is often done for people with risk factors for HIV infection and people who have symptoms of an HIV infection.
• Screen blood, blood products, and organ donors to prevent the spread of HIV.
• Screen pregnant women for HIV infection. The United States Preventive Services Task Force recommends all pregnant women be screened. Pregnant women who are infected with HIV and receive treatment are less likely to pass the infection on to their babies than are women who do not receive treatment.
• Find out if a baby born to an HIV-positive woman also is infected with HIV. PCR is often done in this case because the baby may get antibodies against HIV from the mother and yet not be infected.

The Centers for Disease Control and Prevention (CDC) recommend HIV screening as part of routine blood testing. You and your doctor can decide if testing is right for you.

This test is not done to determine if a person has AIDS. A diagnosis of AIDS means a person is HIV-positive and other problems are present.

How To Prepare

You do not need to do anything before you have this test.

A test for HIV infection can't be done without your consent. Most doctors offer counseling before and after the test to discuss:

• How the test is done, what the results mean, and any other tests that may be done.
• How the diagnosis of an HIV infection may affect your social, emotional, professional, and financial outlooks.
• The benefits of early diagnosis and treatment.

Before the test, it is important to tell your doctor how and where to contact you when your test results are ready. If your doctor has not contacted you within 1 to 2 weeks of your test, call and ask for your results.

How It Is Done

The health professional drawing blood will:

• Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
• Clean the needle site with alcohol.
• Put the needle into the vein. More than one needle stick may be needed.
• Attach a tube to the needle to fill it with blood.
• Remove the band from your arm when enough blood is collected.
• Apply a gauze pad or cotton ball over the needle site as the needle is removed.
• Apply pressure to the site and then a bandage.

How It Feels

You may feel nothing at all from the needle puncture, or you may feel a brief sting or pinch as the needle goes through the skin. Some people feel a stinging pain while the needle is in the vein. But many people do not feel any pain (or have only minor discomfort) once the needle is positioned in the vein. The amount of pain you feel depends on the skill of the health professional drawing the blood, the condition of your veins, and your sensitivity to pain.