Analysis of B19 virus contamination in plasma pools for manufacturing, by using a competitive polymerase chain reaction assay.

BACKGROUND AND OBJECTIVES: The presence of B19 virus in blood poses a risk of transmission of the virus via blood or blood products. Screening processes for manufacturing should be aimed at achieving production plasma pools with B19 virus contamination levels below 104 genome equivalents/ml (geq/ml) in order to prevent transmission of infection through plasma derivatives. MATERIALS AND METHODS: The suitability of a competitor plasmid as an internal analytical standard for the detection of B19 virus in plasma pools was assessed by using a competitive polymerase chain reaction (PCR) assay. Seventy-five plasma pools, each consisting of 960 single donations, were analysed for B19 virus contamination following a lysis treatment. RESULTS: The amount of competitor plasmid in the competitive PCR assay established, with good accuracy, a threshold value for discrimination of the viral load in plasma pools. Analysis of samples from plasma pools showed that 12% of pools were contaminated with B19 virus at levels above the set threshold value. CONCLUSIONS: The competitive PCR assay developed proved to be effective for discrimination of the B19 virus contamination level in screening of plasma pools for manufacturing.