University of Minnesota's Dr. Ashley Haase, using new imaging techniques, showed that the FDC viral pool is much larger than the pool of newly-produced RNA inside of infected cells. We're seeing a lot of additional proliferation and apoptosis in CD4s from infected persons, which drop in accordance with treatment. While potent combination antiretroviral therapy clearly affects these reservoirs, viral residues remain. Moreover, virus could emerge from immunologically privileged sites such as the central nervous system to reinfect peripheral cells. EDTA tubes are the most sensitive, and so the highest viral copy numbers are are recorded when blood is stored in them.
Heparinized tubes are always the least sensitive.
ACD tubes are somewhere in between. And this sort of variability is especially high in patients with very low numbers. Genomic Resistance Doesn't Matter. Oddly, after presenting follow-up data showing that, even in compliant patients, resistance to nevirapine and AZT begins to emerge at 12 months, he seems to have answered his own question.