I have just discovered that there is more than one type of viral load test. How many are there exactly? What are the differences, if any? Is there any one type of test that is more sensitive/better than another? I am treatment naive -- Which test should I recommend my doctor use? What about insurance -- do some cos. pay for one test over another due to price, etc.? I would like to use the "best" or most sensitive test there is.

Thanks.

There are at least 5 companies which have produced viral load assays (Roche, Organon Teknika, Chiron, Genprobe, and Digene)and more probably coming. The Roche Amplicor HIV-1 Monitor is the one currently FDA approved assay. But different reference labs may offer one or two kinds of assays. They all vary somewhat in their technologies, and ease of use for the technician. The current generation of most of these assays have a lower sensitivity of around 50 copies/ml. Different insurance plans may pay for one and not the other. Consistency of the assay between blood draws is probably the most important issue. Although the assays all measure the same thing, the viral loads may vary 1-2 fold between different assays.

MH