"The HIV DNA PCR test measures something different than the HIV antibody Elisa and HIV antibody Western blot assays. The HIV DNA PCR test looks for HIV-1 DNA in the white blood cells of a person, whereas the HIV antibody Elisa and HIV antibody Western blot assays measure the immune response to the virus. If a person has a HIV DNA PCR test, the result may be positive even if insufficient antibodies are present for detection by the HIV antibody EIA"

Katja

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There is a "Western Blot" test too.

The US Center for Disease Control has good information.

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The PCR detects very small amounts of a particular sequence of DNA, which contains the hereditary information of cells. For HIV diagnosis, the PCR test is used to detect genetic information inserted into the DNA of human cells by HIV. The test can measure levels previously considered "undetectable". The advantage of the PCR test is that it is a direct test for the presence of the AIDS virus. If you are infected, the DNA of the AIDS virus is present in your blood. Just what is PCR? PCR stands for polymerase chain reaction. PCR is a technique to look for unique DNA. PCR for the AIDS virus looks for DNA of the AIDS virus

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Please be careful to check everything you see on the web with the CDC site. There is a lot of bad information out there.

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Anyway, I guess there is always a certain time window until the virus/ the antibodies (may it be 30 days or 60) can be found in the blood - no matter what test you pick.

Katja

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