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Clarifying The Western Blot Test

The Western Blot test is one of the two main tests offered by allopathic medicine for Lyme disease. There are a few things that are really helpful to know about this test, which I want to share here. Those of you who took my Lyme Versed Course will have already learned this, but it's good to have the reminder.

Here are some simple facts:

  • The Western Blot test is specific to Borrelia burgdorferi bacteria (this is ONE strain of borrelia. There are many different strains. 100 known in the US. 300. known worldwide)

  • This test does NOT test for the presence of Lyme, nor the presence of microbes. It is indirectly looking at antibodies made by the body against this one strain of borrelia.

  • It tests for IgM (current or recent infection) antibodies AND it tests for IgG (past infection - this is your chronic Lyme)

  • This is a decent test for what it is testing for. It has poor diagnostic criteria.

Reading the Western Blot:

  • The Western Blot test is composed of different bands. IgM and IgG bands.

  • A positive IgM may indicate a recent infection.

  • A positive IgG may indicate an established, chronic infection.

  • In order to get a positive IgM, two of the following three bands must be positive: OSPC (22-25), 39,41.

  • In order to get a positive IgG, 5 of the following bands must be positive: 18, OSPC (22-25), 28, 30,39,41,45,58,66,93.

  • Bands 21 and 25, 31,34,39 are thought to be highly specific to Lyme.

  • Band 41 is a non-Lyme specific antibody that often comes up positive.

the trouble with the diagnostics is the number of bands needed to be given a positive diagnosis. If you dont make the cut, you are given a negative. However, we must look at those bands that are highly specific to Lyme. IF one or two of those is positive, even if you get a negative on the Western Blot test, it warrants further investigation and more in depth testing.

Always ask for a copy of your test that shows the bands, so that you can determine if you are in fact coming up negative, or if you may actually be positive.

Also, keep in mind that this test only tests for that one strain. Other strains of borrelia can cause Lyme disease. It also does not test for any of the co-infections. So while you may have a negative on this test, it doesn't touch on whether Babesia, bartonella, powassan, or any of the other 19 known co-infections may be present.

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It can be hard to sometimes access testing for Lyme, EBV, etc. AND........thankfully there are resources that can help folks order their own testing that they can bring to a lab (hopefully one not to


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