Summary
Human parvovirus B19 (B19) DNA has frequently been detected in plasma-derived coagulation
factor concentrates. Furthermore, transmission of B19 infection was observed, indicating
presence of the infectious virus despite routine viral inactivation/removal procedures
during the manufacturing process. Recently, human parvovirus DNA isolates, variant
from B19, have been identified resulting in classification of B19 virus into three
distinct genotypes, with all viruses previously classified as B19 belonging to genotype
1. So far, there is no information available on contamination of clotting factor concentrates
with genotype 2. Therefore, we analysed 202 different factor concentrate lots for
genotype 1 and 2 DNA by PCR. Analysis of one hundred eighty-one lots representing
13 different products, administered over the last three years, was compared to 21
lots (8 products) used until the early 1980s which had not been treated by viral inactivation
procedures. Genotype 1 DNA was detected in 77/181 (42.5%) currently administered lots,
and 17/21 (81%) previously used lots. The level of genotype 1 DNA contamination was
similar in currently and previously administered concentrates. Genotype 2 DNA was
found in 5/202 (2.5%) lots, all of which were co-contaminated with genotype 1 DNA.
DNA sequence analysis showed that the PCR-double positive concentrates contained typical
genotype 1 and genotype 2 DNA. Because genotype 2 appears to cause a similar spectrum
of diseases as genotype 1, simultaneous detection of genotype 2 by nucleic acid amplification
testing (NAT), now widely applied to plasma pools for genotype 1, would give an added
level of safety to blood products.
Keywords
Human parvovirus - genotype 2 - coagulation factor concentrates