Novel Human Erythrovirus Associated with Transient Aplastic Anemia

Abstract

Erythrovirus (formerly parvovirus) B19 causes a wide range of diseases in humans, including anemia due to aplastic crisis. Diagnosis of B19 infection relies on serology and the detection of viral DNA by PCR. These techniques are usually thought to detect all erythrovirus field isolates, since the B19 genome is known to undergo few genetic variations. We have detected an erythrovirus (V9) markedly different from B19 in the serum and bone marrow of a child with transient aplastic anemia. The B19 PCR assay yielded a product that hybridized only very weakly to the B19-specific probe and whose sequence diverged more from those of 24 B19 viruses (11 to 14%) than the divergence found within the B19 group (≤6.65%). Restriction enzyme analysis of the V9 genome revealed that this genetic divergence extended beyond the amplified region. Interestingly, serological tests failed to demonstrate a response characteristic of acute B19 infection. V9 could be a new erythrovirus, and new diagnostic tests are needed for its detection.

Different susceptibility of B19 virus and mice minute virus to low pH treatment

“…The question remains whether the recently described new Erythrovirus genotypes (genotype 2, e.g., A6; genotype 3, e.g., V9 according, Servant et al 22 ) behave the same way. [23][24][25] The fact that DNA accessibility could still be measured after shifting pH up to 7.5 (conditions for DNase treatment) showed that the low pH-and/or temperatureinduced erythrovirus capsid disintegration is irreversible. This is of special interest because for some viruses reversible conformational changes of the capsid induced by temperature and pH were reported.…”

Parvovirus B19: implications for transfusion medicine. Summary of a workshop

“…Recently, B19 variants have been described 39 ; these variants may be missed if only PCR is used, depending on the primers chosen for amplification. Studies using direct hybridization assays and longer probes should be capable of detecting strains with less than 10 percent sequence variation.…”

Human Parvovirus B19: A New Emerging Pathogen of Inflammatory Cardiomyopathy

“…The genetic diversity among PVB19 isolates has been reported to be very low, with <1-2% nucleotide divergence in the whole genome (Hicks et al, 1996;Nguyen et al, 1999;Hokynar et al, 2002). However, some isolates obtained from patients with persistent PVB19 infection have been reported to exhibit a higher degree of variability in some parts of the genome, with the VP1 region being the most variable at both the DNA and protein levels with up to 4% and 8% divergence respectively (Hemauer et al, 1996).…”