Open AccessEvaluation of 2012 US EHDV-2 outbreak isolates for genetic determinants of cattle infection
Author(s) -
Erin E. Schirtzinger,
Dane C. Jasperson,
Mark G. Ruder,
David E. Stallknecht,
Christopher Chase,
Donna J. Johnson,
Eileen N. Ostlund,
William C. Wilson
Publication year - 2019
Publication title -
journal of general virology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.55
H-Index - 167
eISSN - 1465-2099
pISSN - 0022-1317
DOI - 10.1099/jgv.0.001221
Subject(s) - outbreak , biology , serotype , virology , phylogenetic tree , veterinary medicine , genetics , gene , medicine
Following a summer of severe drought and abnormally high temperatures, a major outbreak of EHDV occurred during 2012 in the USA. Although EHDV-1, -2 and -6 were isolated, EHDV-2 was the predominant virus serotype detected during the outbreak. In addition to large losses of white-tailed deer, the Midwest and northern Plains saw a significant amount of clinical disease in cattle. Phylogenetic analyses and sequence comparisons of newly sequenced whole genomes of 2012 EHDV-2 cattle isolates demonstrated that eight of ten EHDV-2 genomic segments show no genetic changes that separate the cattle outbreak sequences from other EHDV-2 isolates. Two segments, VP2 and VP6, did show several unique genetic changes specific to the 2012 cattle outbreak isolates, although the impact of the genetic changes on viral fitness is unknown. The placement of isolates from 2007 and 2011 as sister group to the outbreak isolates, and the similarity between cattle and deer isolates, point to environmental variables as having a greater influence on the severity of the 2012 EHDV outbreak than viral genetic changes.