Detection of human parvovirus B19 DNA in plasma pools and blood products derived from these pools: implications for efficiency and consistency of removal of B19 DNA during manufacture.

The polymerase chain reaction (PCR) assay was used to detect human parvovirus B19 DNA in 38 blood products and start plasma pools from five different manufacturers. The products examined were albumin, factor VIII, intravenous (i.v.) and intramuscular (i.m) immunoglobulin batches. The majority of pools from all the manufacturers had detectable B19 DNA (64/75:85%; ranging from 60% to 100% for individual manufacturers). B19 DNA was found in 3/12 albumin samples, in 7/7 factor VIII samples, 3/15 IVIG samples and 3/4 IMIG samples. The levels of B19 DNA in pools varied from 10(2) to 10(9) genome equivalents/ml, whereas the levels in products varied from 10(2) to 10(6) genome equivalents/ml, but there was no clear relationship between the levels of B19 DNA in start pools and final products. The levels of B19 DNA varied between different batches of the same product from a single manufacturer, possibly due to small variations in the processing parameters. In addition, there was some indication from the study of IVIG samples that treatment at low pH may result in removal of PCR-detectable B19 DNA.