LightCycler consensus PCR for rapid and differential detection of human erythrovirus B19 and V9 isolates.

Until recently, B19 virus was considered to be the only human pathogen of the genus erythrovirus. However, other non-B19 virus strains, such as V9, have now been isolated and are thought to cause infections clinically and serologically indistinguishable from those caused by B19 virus. Whereas B19 virus related isolates have a low genetic diversity of only 1-2%, nucleotide disparity of up to 12% was found for the new isolates, suggesting that non-B19 virus isolates may not be detectable using B19 virus specific PCR methods. To overcome this problem, we designed consensus primers and probes to enable the simultaneous detection of both B19 and non-B19 virus and subsequent discrimination of the two lineages by melting temperature (T(m)) analysis. A total of 196 clinical specimens, from 185 patients with a history of or an anamnesis resembling B19 virus infection, were analyzed using the consensus PCR test. Erythrovirus DNA was detected in 37 of these samples and was found to be B19 virus specific in each case, confirming previous results using B19 virus specific PCR. Although no non-B19 virus DNA was detected in any of the clinical samples tested in this study, more extensive studies are warranted. The routine use of erythrovirus consensus PCR in the diagnosis of B19 virus infection should provide valuable information on the epidemiology and clinical role of non-B19 virus isolates; its use in screening would increase the safety of blood products.