Genomic sequencing of deer tick virus and phylogeny of powassan-related viruses of North America.

Abstract

Abstract. Powassan (POW) virus is responsible for central nervous system infection in humans in North America and the eastern parts of Russia. Recently, a new flavivirus, deer tick (DT) virus, related to POW virus was isolated in the United States, but neither its pathogenic potential in human nor the taxonomic relationship with POW virus has been elucidated. In this study, we obtained the near-full-length genomic sequence of the DT virus and complete sequences of 3 genomic regions of 15 strains of POW-related virus strains. The phylogeny revealed 2 lineages, one of which had the prototype POW virus and the other DT virus. Both lineages can cause central nervous system infection in humans. By use of the combination of molecular definition of virus species within the genus Flavivirus and serological distinction in a 2-way cross-neutralization test, the lineage of DT virus is classified as a distinct genotype of POW virus.

Virome Analysis of Amblyomma americanum, Dermacentor variabilis, and Ixodes scapularis Ticks Reveals Novel Highly Divergent Vertebrate and Invertebrate Viruses

“…Two lineages of Powassan virus (POWV; family Flaviviridae, genus Flavivirus) circulate in the United States: lineage I, isolated mainly from Ixodes cookei, and lineage II (also known as deer tick virus), detected predominately in I. scapularis (29). Human infection with viruses from either lineage has been linked with Powassan encephalitis, a severe, potentially life-threatening neurological illness (29,30). POWV lineage II has been detected in I. scapularis throughout the Northeast (23,31,32).…”

Prevalence and Genetic Characterization of Powassan Virus Strains Infecting Ixodes scapularis in Connecticut

“…These data are consistent with previous analyses. 8,10,18 The POW lineage included the virus isolated from I. cookei collected in Old Lyme, CT during 1978. The remaining Connecticut viruses were isolated from I. scapularis, and all grouped within the DTV lineage.…”

“…[3][4][5][6][7] Powassan virus comprises two distinct genotypes, each with a distinct natural history and are known as POW (lineage 1) and deer tick virus (DTV) (lineage 2). [8][9][10] The POW lineage is maintained in an enzootic cycle involving mainly Ixodes cookei and Ixodes marxi and medium-sized mammals, such as red squirrels, Tamiasciurus hudsonicus, groundhogs, Marmota monax, and skunks, Mephitis sp., 1,11 whereas the DTV lineage has been isolated primarily from Ixodes scapularis. 1 Both lineages have been isolated from ticks, 11,12 and both have been isolated or detected in tissues from fatal human cases of encephalitis.…”

The Biological Survey of Canada: A Personal History

“…From phylogenetic analysis of the genomes of Powassan virus isolates, two lineages of the virus are recognised in North America (Ebel et al 2001;Kuno et al 2001). The genetic lineage that includes the prototypic Powassan virus is distinct from a lineage associated with virus isolates from I. scapularis.…”