Digital PCR provides absolute quantitation of viral load for an occult RNA virus

► Occult RNA virus GBV-C viral load was measured directly using microfluidic RT-dPCR. ► RT-dPCR has a greater precision than RT-qPCR, because of lower CV/SEM and higher direction limit. ► THP-1, a monocytic derived cell line, had positive GBV-C replication.