HIV testingis typically a multi-step process.
The first test used is generally a high sensitivity test.
High sensitivity tests are designed to detect as many potential HIV infections as possible.
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How Does the Western Blot Test Work?
Western blots tests are also known as protein immunoblots.
These tests are used to detect specific proteins in a sample.
The basic technique of a Western blot involves sorting proteins by length on a gel.
Then that grid is probed with antibodies that react to the specific proteins that are being searched for.
The exact algorithm for declaring a result indeterminate varies for each specific Western blot test.
Indeterminate Western blot results may be a sign of anew HIV infection.
That means they are less likely to detect an infection.
There are a number of reasonsunrelated to HIV exposurethat can cause such a result.
Immediate retesting checks to see whether there was a flaw in the way the Western blot was run.
Retesting will often resolve an indeterminate Western blot test into a clearly positive or negative result.
No single HIV test is ideal in every situation.
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