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HIV test info and new HIV theory
Oct 21, 1996

Hi, I was wondering just what the procedure is in the US regarding the HIV test. When someone is tested, is the ELISA test or the WB test used? What circumstances dictate which test should be used on whom? Are they equally accurate or are they designed to have different purposes? In the event that the two tests give conflicting results, which one is considered correct? What does "negative," "positive," and "inconclusive," mean at 3 mo. and how do the ELISA and WB tests lead to these conclusions? Also, I have one more question: I heard a theory somewhere that AIDS is NOT caused by HIV but instead is a breakdown of the immune system due to the long term use of drugs... i.e. that HIV is just another harmless carrier virus. What are your comments on this?

Response from Mr. Sowadsky

Hi. Thank you for your questions. When a person gets an antibody test for HIV, the first test that is done is the ELISA test, also called the EIA test. If this test is repeatedly positive, it will be confirmed with a confirmatory test (usually a Western Blot or an IFA test). This second test can be done from the same tube of blood. You must test positive on both the ELISA test and the confirmatory test to be considered HIV positive.

If the ELISA test is negative, this is considered a negative result, and confirmatory tests are not necessary. A negative result means that no antibodies were found. If the ELISA test is repeatedly positive but the confirmatory test is negative, this is considered a negative result overall. If both the ELISA test and the confirmatory test are positive, this is considered a positive result. This means that antibodies were found, and the person is infected with HIV.

ELISA tests are either positive or negative. Western Blot tests can be positive, negative, or indeterminate. An indeterminate test means that the test could not determine whether a person is infected or not. This can be due to 2 things. Either a person was so recently infected that they are just starting to produce antibodies, or something else is cross reacting on the test. If an indeterminate test result occurs, the person is usually re-tested in about 4-6 weeks to determine whether they are infected or not.

False negatives on these tests could occur if you take the test too soon. The average period of time from infection to testing positive is 25 days. This is an average, so many people may take longer than 25 days to show positive. At 3 months, most, but not all, infected people will test positive on the tests. At 6 months, more than 99% of infected people will show positive on the tests. This is as accurate as the test could ever be. As an example, if a person were to take the test at 2 weeks post exposure, if they got a negative result, they could be infected and the test just didn't pick it up yet. This is called a false negative. However, false negatives beyond 6 months are extremely rare. False positive results on confirmatory tests are also extremely rare, and are usually due to laboratory error.

The ELISA test is very good at picking up infections, but sometimes gives false positive readings (which is why confirmatory testing is always done on positive ELISA results). The Western Blot is very good at ruling out false positive ELISA tests. In other words, the ELISA test is very good at giving a positive result when a person is truely positive. The Confirmatory tests, like the Western Blot, are very good at giving a negative result when the person is truely negative. Hence, the two tests used together are very good at determining whether a person is infected or not.

As to the comment that "AIDS is NOT caused by HIV but instead is a breakdown of the immune system due to the long term use of drugs... i.e. that HIV is just another harmless carrier virus."

This has been definitively proven to be totally incorrect. Most of the people in the world with AIDS do not use drugs and there is absolutely no evidence that they are immunosupressed because of drugs. All of the proven scientific evidence shows that HIV is indeed the cause of AIDS, and is not in any way a harmless carrier virus. If you'd like, I can mail you (by conventional mail) written information that reviews the medical literature which proves that HIV is the cause of AIDS. There are some people out there who claim that HIV is not the cause of AIDS. However, years of scientific data strongly prove otherwise. If you have any further questions, please feel free to call the Centers for Disease Control at 1.800.232.4636 (Nationwide). Rick Sowadsky MSPH CDS



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