Genetic diversity and distribution of Peromyscus-borne hantaviruses in North America

The 1993 outbreak of hantavirus pulmonary syndrome (HPS) in the southwester n United States was associated with Sin Nombre virus, a rodent-borne hantav irus; The virus' primary reservoir is the deer mouse (Peromyscus maniculatu s). Hantavirus-infected rodents were identified in various regions of North America. An extensive nucleotide sequence database of an 139 bp fragment a mplified from virus M genomic segments was generated. Phylogenetic analysis confirmed that SNV-like hantaviruses are widely distributed in Peromyscus species rodents throughout North America. Classic SNV is the major cause of HPS in North America, but other Peromyscine-borne hantaviruses, e.g., New York and Monongahela viruses, are also associated with HPS cases. Although genetically diverse, SNV-like viruses have slowly coevolved with their rode nt hosts. We show that the genetic relationships of hantaviruses in the Ame ricas are complex, most likely as a result of the rapid radiation and speci ation of New World sigmodontine rodents and occasional virus-host switching events.