IDENTIFICATION OF A NOVEL SIMIAN PARVOVIRUS IN CYNOMOLGUS MONKEYS WITH SEVERE ANEMIA - A PARADIGM OF HUMAN B19 PARVOVIRUS INFECTION

Although human B19 parvovirus infection has been clearly associated wi th a number of distinct syndromes (including severe anemia, abortion, and arthritis), detailed knowledge of its pathogenesis has been hinder ed by the lack of a suitable animal model. We have identified a novel simian parvovirus in cynomolgus monkeys with severe anemia. Sequencing of a 723-bp fragment of cloned viral DNA extracted from serum reveale d that the simian parvovirus has 65% homology at the DNA level with th e human B19 parvovirus but little homology with other known parvovirus es. Light microscopic examination of bone marrow from infected animals showed intranuclear inclusion bodies, and ultrastructural studies sho wed viral arrays characteristic of parvoviruses. Another striking feat ure was the presence of marked dyserythropoiesis in cells of the eryth roid lineage, raising the possibility that B19 parvovirus infection ma y underlie related dyserythropoietic syndromes in human beings. Affect ed animals had concurrent infection with the immunosuppressive type D simian retrovirus, analogous to HIV patients who develop severe anemia because of infection with B19 parvovirus. The remarkable similarities between the simian and B19 parvoviruses suggest that experimentally i nfected cynomolgus monkeys may serve as a useful animal model of human B19 infection.