PARKVILLE VIRUS - A NOVEL GENETIC VARIANT OF HUMAN CALICIVIRUS IN THESAPPORO VIRUS CLADE, ASSOCIATED WITH AN OUTBREAK OF GASTROENTERITIS IN ADULTS

This report describes the characterization of Parkville virus, the eti ologic agent of an outbreak of foodborne gastroenteritis, that has the morphology of a calicivirus and genetic properties that distinguish i t from previously identified strains in the Sapporo/Manchester virus c lade. Sequence analysis of the Parkville virus genome showed it contai ned the RNA-dependent RNA polymerase motifs GLPSG and YGDD characteris tic of members of the family Caliciviridae with an organization identi cal to that reported for the Manchester virus where the capsid region of the polyprotein is fused to the RNA polymerase. Parkville virus how ever, demonstrates considerable sequence divergence from both the Manc hester and Sapporo caliciviruses, providing the first indications that genetic diversity exists within caliciviruses of this previously homo geneous clade. On the basis of recent advances in the genetic characte rization of members of the family Caliciviridae, we propose a new inte rim phylogenetic classification system in which Parkville virus would be included with Manchester and Sapporo virus as a separate group dist inct from the small round-structured viruses (Norwalk-like viruses) th at also cause diarrhea in humans. (C) 1997 Wiley-Liss, Inc.