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Understand Your HIV Test
Only an HIV Test Can Tell if You are Infected

By , About.com Guide

Updated: December 13, 2009

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Getting an HIV test is easy; understanding an HIV test is not so easy. There is more than one type of HIV test used to determine if a person has been infected with HIV. These tests detect different substances in the blood that are present when a person has been infected with HIV. One detects HIV proteins that circulate in the body after a person has been infected. Two others detect HIV antibodies that have been produced by the body after HIV infection has occurred. Let's look a little closer at the HIV test.

Elisa

This is the first step of an HIV test. This test detects the presence of HIV antibodies in the blood. If the test is negative then the person is determined not to be HIV infected and testing stops there. If the test is positive the second step of the test is run to confirm the positive results of the first step.

Western Blot

This test is used to confirm the positive Elisa test results. The Western Blot test detects specific protein bands that are present in an HIV infected individual. In combination with a positive Elisa, a positive Western Blot is 99.9 percent accurate in detecting that HIV infection has occurred.

HIV PCR

The HIV PCR test detects specific Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA) sequences that indicate the presence of HIV in the genetic structure of anyone HIV infected. After HIV infection occurs, RNA and DNA from the HIV virus circulates in the blood. The presence of these DNA and RNA "pieces" indicates the presence of HIV virus.

The HIV Life Cycle - In Pictures

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