Although the reservoir of this virus is yet unknown it is likely in a tissue compartment and not predominantly in cells migrating through blood.
Questions arising from this case are how and why this certainly defective variant emerged during efficient virosuppression, and how it could be preferentially and stably produced.
As for interpretation of residual viremia found in long-term treated patients with undetectable viral load, virus production can originate from on-going replication, but the cells had to be continuously co-infected with the two viral forms, or synthesis by chronically infected cells. However, the defective virus production at detectable level suggests unusual circumstances.
Anyway, this case raises concern about the possible long term synthesis of defective viruses.