Novel serotype of bluetongue virus in South America and first report of epizootic haemorrhagic disease virus in Ecuador

Abstract

SummaryBluetongue virus (BTV) and Epizootic haemorrhagic disease virus (EHDV) are closely related Orbiviruses that affect domestic and wild ruminants. In Ecuador previous serological studies reported the presence of BTV; however, no data are available about the presence of EHDV. In this study, 295 cattle without symptoms of infection were sampled from two farms located in Andean and Amazonian regions and from a slaughterhouse in the coastal region. ELISA analyses showed high prevalence of BTV (98.9%) and EHDV (81.3%) antibodies, and RT-qPCRs revealed the presence of EHDV (24.1%) and BTV (10.2%) genomes in cattle blood samples. Viral isolation allowed to identify EHDV serotype 1 (EHDV1) and BTV serotypes 9 (BTV9), 13 and 18. These findings suggest that BTV and EHDV are enzootic diseases in Ecuador.

Ecological Dynamics Impacting Bluetongue Virus Transmission in North America

“…Coincident with this invasion of novel serotypes in Europe and elsewhere, 11 previously exotic serotypes (serotypes 1, 3,5,6,9,12,14,18,19,22,24) have been isolated in the southeastern US since 1999 (39). Four serotypes (serotypes 10,11,13,17) have long been enzootic throughout much of the US (40,70,71).…”

“…Novel BTV serotypes have also recently been identified in historically enzootic countries or regions including the southeastern United States (US), South America, Israel, and Australia, reflecting diverse means for spread of these viruses between regions (13,(19)(20)(21)(22). Despite the link of climate change to recent incursions of BTV in Europe and expansion of geographic range in North America, there is limited information on how factors related to the ecology of BTV's vertebrate and invertebrate hosts might impact the evolution, distribution, and transmission dynamics of BTV (1,23,24).…”

Detección molecular del virus de Lengua Azul en Culicoides insignis y en ovinos de Pucallpa, Perú

“…La prueba de ELISAc posee 99% de especificidad y 100% de sensiblidad en la detección del VLA, ya que interviene un anticuerpo monoclonal que detecta un epitopo específico en la proteína VP7 del VLA (Reddington et al, 1991;VMRD, 2005 En América del Sur, anticuerpos contra el VLA han sido detectados en ovinos de Ecuador (8%), Venezuela (94.7%) y Argentina (95%), en bovinos de Colombia (51.8%), y en búfalos (25.9-93%) y pecaries (39%) de Brasil (Lager, 2004). Cabe mencionar que algunos de estos resultados serológicos han sido realizados mediante la prueba de IDGA, por lo que es difícil afirmar que los anticuerpos detectados sean inducidos por VLA, ya que existen evidencias de la presencia del VEHE en la región sudamericana (Homan et al, 1985;Verdezoto et al, 2018). No obstante, estos estudios demuestran la amplia distribución del VLA, así como, uno o más vectores competentes de su transmisión en el continente sudamericano (Meiswinkel et al, 2004; Darpel et al, 2011).…”

Quantitative RT-PCR assays for identification and typing of the Equine encephalosis virus

“…The long-distance movement of viruses (including different orbiviruses) has been identified between continents and has been linked to increased human travel and international trade [11][12][13]. Several distinct and novel orbiviruses have been detected or isolated in South America, although the threats that they pose to the health of domesticated and wild animals (including horses) have not been fully evaluated [14]. Peruvian horse sickness virus is a mosquito-transmitted orbivirus first isolated in 1979 (with a case fatality rate of7 8%) that shows a high level of nucleotide sequence similarity to the Elsey Station virus (ELSV) from Australia [15].…”

“…Peruvian horse sickness virus is a mosquito-transmitted orbivirus first isolated in 1979 (with a case fatality rate of7 8%) that shows a high level of nucleotide sequence similarity to the Elsey Station virus (ELSV) from Australia [15]. The Rioja virus, which was also isolated from donkeys and mosquitoes in Peru, is closely related to Yunnan orbivirus from China [14], indicating that simple geographic separation is not sufficient to completely remove the risk of Orbivirus introductions and emergence of the diseases they cause [15,16]. Although Brazil currently appears to be free of EEV, it has large arthropod populations of known Orbivirus vector species as well as susceptible equine hosts and any future introductions could cause significant disease outbreaks.…”