Genetic and phylogenetic analysis of the outer-coat proteins VP2 and VP5 of epizootic haemorrhagic disease virus (EHDV): Comparison of genetic and serological data to characterise the EHDV serogroup

Detection of a novel reassortant epizootic hemorrhagic disease virus (EHDV) in the USA containing RNA segments derived from both exotic (EHDV-6) and endemic (EHDV-2) serotypes

“…Additionally, topotypes of EHDV-1 and EHDV-2 are present in Australia, which, although genetically divergent from analogous North American serotypes, share common neutralization epitopes (Gould & Pritchard, 1991;Weir et al, 1997). IBAV, which is now recognized, as has previously been suggested, as a topotype of EHDV-2, has been associated with periodic outbreaks in cattle in East Asia since its first description during a large-scale epizootic in Japan involving 40 000 cattle in 1959 (Omori et al, 1969;Bak et al, 1983;Liao et al, 1996;Uchinuno et al, 2003;Anthony et al, 2009).…”

“…Three serotypes have been recognized in Africa: EHDV-3 (proposed to be EHDV-1) and EHDV-4, which were initially isolated from Culicoides spp. in Nigeria in 1967and 1968, respectively (Lee et al, 1974, and EHDV-318 (proposed to be EHDV-6), which was first isolated from cattle in Bahrain in 1983 and subsequently described from sentinel calves in the Sudan (Mohammed & Mellor, 1990;Rabenau et al, 1993;Anthony et al, 2009). EHDV serotypes 5, 7 and 8, along with the prototype strain of EHDV-6 (CSIRO 753), were initially isolated from sentinel cattle herds in Queensland and the Northern Territory of Australia during 1977-1982(St George et al, 1983.…”

Epizootic haemorrhagic disease

“…All EHDVs share common group antigens that distinguish them from BTV, African horse sickness virus, and other orbiviruses. There is confusion in the historical literature regarding the number of serotypes of EHDV, but the International Committee for Taxonomy of Viruses now designates just seven serotypes of the virus based on recent serological and molecular analyses (65,66,67,68,69). Ibaraki virus was initially classified as EHDV-7, but is now classified as EHDV-2, as it is genetically and serologically most similar to the prototype strain of EHDV-2 that was isolated in Alberta, Canada, in 1964.…”

“…Each gene segment encodes at least one protein and the coding assignments and functions of each protein are assumed to be identical to those of BTV. The icosahedral EHDV virion includes seven structural proteins (VP1-7) and at least four non-structural viral proteins (NS1, NS2, NS3, NS3A) are produced in EHDV-infected cells (4,65,66,67,68). VP2 and VP5 form the outer capsid of the EHDV virion, and VP2 is responsible for serotype determination.…”

An improved Real-Time Polymerase Chain Reaction for the Simultaneous Detection of All Serotypes of Epizootic Hemorrhagic Disease Virus

“…1,15 These studies indicate that serotype 3 is not a separate group but rather a member of type 1 and, therefore, conclude that there are only 7 distinct serotypes of EHDV. 1 Whereas several serotypes of EHDV can be distinguished worldwide, most cases of hemorrhagic disease observed in white-tailed deer in North America can be attributed to EHDV serotypes 1 and 2. 9 Epizootic hemorrhagic disease virus is transmitted by species of Culicoides midges.…”