Molecular testing for parvoviruses

Within the family Parvoviridae, parvovirus B19 (B19V) is the most relevant human pathogenic virus. B19V shows a selective tropism for erythroid progenitor cells, where it can achieve a productive infection and exert a cytotoxic effect that may lead to a transient block in erythropoiesis. Infection is characterized by a viremic phase that is progressively controlled by the development of a specific immune response, and is associated not only to hematological disorders but also to a wide range of pathologies, including erythema infectiosum, arthralgias, myocarditis, and fetal infections possibly leading to fetal deaths. Diagnosis of B19V infection takes advantage from a multiparametric approach, combining the determination of the immune status with a direct molecular detection of the viral genome, with qPCR as the method of choice to obtain reliable information on the viral load, a parameter critical to a clinical assessment of the infectious process. Molecular diagnostic methods for B19V are essential for confirmation of acute infections, discrimination of persistent infections, in antenatal screening and diagnosis of fetal infections. In addition to B19V, human bocaviruses have gained interest as respiratory or enteric pathogenic viruses, while human tetraparvovirus and bufavirus remain elusive in their association to disease.