Bovine Ephemeral Fever Viruses in Israel 2014-2023: Genetic Characterization of Local and Emerging Strains.

Bovine ephemeral fever (BEF) is an arthropod-borne viral disease, which frequently causes significant epizootics in susceptible water buffalo and cattle in Africa, Australia, Asia and the Middle East. In the current study, a two-stage protocol for BEFV viral isolation was developed. Data on the clinical signs, geographic distribution and phylogenetic analysis of BEFV strains isolated in Israel in 2015, 2018, 2021 and 2023 were summarized.

Development of two competitive ELISAs based on monoclonal antibodies for the serological detection of Bovine ephemeral fever virus.

Bovine ephemeral fever virus (BEFV) is a member of the genus Ephemerovirus in the family Rhabdoviridae. It is an arthropod-borne virus transmitted by many species of midges and mosquitoes. It can cause severe economic consequences due to losses in milk production and the general condition of cattle and water buffalo.

Comparative Molecular and Epidemiological Analyses of Israeli Bluetongue Viruses Serotype 1 and 9 Causing Outbreaks in 2018-2020.

Israel is endemic to bluetongue virus (BTV). The introduction of novel-for-the-region arboviruses have been recorded annually in recent years. In 2019, previously non-reported in-the-country BTV-1 and BTV-9 were identified.

Characterization of experimental Shuni virus infection in the mouse.

Shuni virus (SHUV), an orthobunyavirus of the Simbu serogroup, was initially isolated in Nigeria in the 1960s, further detected in other African countries and in the Middle East, and is now endemic in Israel. Transmitted by blood-sucking insects, SHUV infection is associated with neurological disease in cattle and horses, and with abortion, stillbirth, or the birth of malformed offspring in ruminants. Surveillance studies also indicated a zoonotic potential.

Identification of Novel Reassortant Shuni Virus Strain in Clinical Cases of Israeli Ruminants, 2020-2021.

The Shuni virus (SHUV) causes an endemic viral infection in Israel and South Africa. It belongs to the Simbu serogroup within the order , family , genus . Recently, it has been identified in aborted cases of domestic ruminants, young cattle and horses manifesting neural signs and acute death, symptomatic cows, and in carcasses of wild animals.

Identification and Genetic Characterization of Viral Pathogens in Ruminant Gestation Abnormalities, Israel, 2015-2019.

Infectious agents including viruses are important abortifacients and can cause fetal abnormalities in livestock animals. Here, samples that had been collected in Israel from aborted or malformed ruminant fetuses between 2015 and 2019 were investigated for the presence of the following viruses: the reoviruses bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV), the flaviviruses bovine viral diarrhea virus (BVDV) and border disease virus (BDV), the peribunyaviruses Shuni virus (SHUV) and Akabane virus (AKAV), bovine herpesvirus type 1 (BoHV-1) and bovine ephemeral fever virus (BEFV). Domestic (cattle, sheep, goat) and wild/zoo ruminants were included in the study.

Genomic Analysis Illustrated a Single Introduction and Evolution of Israeli Bluetongue Serotype 8 Virus Population 2008-2019.

Outbreaks of the European Bluetongue virus (BTV) serotype 8 (BTV-8), which are characterized by activity cycles separated by years of inactivity, may be influenced by genetic changes of the virus or by herd immunity. BTV activity in Israel is characterized by similar dynamics, but differs from European countries in its vector population, environmental conditions, and lack of cattle vaccination against this serotype. Comparison of these two geographical systems and characterization of their epidemiological connection is therefore of high interest in-order to better understand the factors influencing BTV-8 evolution.

Shuni virus-induced meningoencephalitis after experimental infection of cattle.

Shuni virus (SHUV), an insect-transmitted orthobunyavirus of the Simbu serogroup within the family Peribunyaviridae, may induce severe congenital malformations when naïve ruminants are infected during gestation. Only recently, another clinical presentation in cattle, namely neurological disease after postnatal infection, was reported. To characterize the course of the disease under experimental conditions and to confirm a causal relationship between the virus and the neurological disorders observed in the field, six calves each were experimentally inoculated (subcutaneously) with two different SHUV strains from both clinical presentations, that is encephalitis and congenital malformation, respectively.

Bluetongue Serotype 3 in Israel 2013-2018: Clinical Manifestations of the Disease and Molecular Characterization of Israeli Strains.

In this paper, the results of the diagnostic activities on Bluetongue virus serotype 3 (BTV-3) conducted at Kimron Veterinary Institute (Beit Dagan, Israel) between 2013 and 2018 are reported. Bluetongue virus is the causative agent of bluetongue (BT), a disease of ruminants, mostly transmitted by competent species. In Israel, BTV-3 circulation was first detected in 2013 from a sheep showing classical BT clinical signs.

Complete Coding Sequence of a Novel Bluetongue Virus Isolated from a Commercial Sheeppox Vaccine.

The full genome sequences of two isolates of bluetongue virus (BTV) from a commercial sheeppox vaccine were determined. Strain SPvvvv/02 shows low sequence identity to its closest relative, strain BTV-26 KUW2010/02, indicating the probable detection of a novel BTV genotype, whereas strain SPvvvv/03 shows high sequence identity to strain BTV-28/1537/14.

Characterization of bluetongue virus serotype 28.

Bluetongue virus (Reoviridae; Orbivirus, BTV), which is usually transmitted by biting midges, affects wild and domestic ruminants worldwide, thereby causing an economically important disease. Recently, a putative new BTV strain was isolated from contaminated vaccine batches. In this study, we investigated the genomic and clinical characteristics of this isolate, provisionally designated BTV-28.

Emergence of a Novel Reassortant Strain of Bluetongue Serotype 6 in Israel, 2017: Clinical Manifestations of the Disease and Molecular Characterization.

Reassortment contributes to the evolution of RNA viruses with segmented genomes, including Bluetongue virus (BTV). Recently, co-circulation of natural and vaccine BTV variants in Europe, and their ensuing reassortment, were proposed to promote appearance of novel European BTV strains, with potential implications for pathogenicity, spread and vaccination policies. Similarly, the geographical features of the Mediterranean basin, which spans over portions of three continents, may facilitate the appearance of clinically relevant reassortants via co-circulation of BTV strains of African, Asian and European origins.

Detection of Epizootic Hemorrhagic Disease Virus Serotype 1, Israel.

During September 2016-February 2017, we detected epizootic hemorrhagic disease virus (EHDV) in ruminants in Israel. BLAST and phylogenetic analyses of segment 2 in 6 EHDVs isolated from field samples indicated a close relationship to the EHDV serotype 1 strain in Nigeria. Affected cattle had mostly mild or asymptomatic disease.

Shuni virus in Israel: Neurological disease and fatalities in cattle.

The insect-transmitted Shuni virus (SHUV) belongs to the Simbu serogroup of orthobunyaviruses and it is known to induce abortions, stillbirths and severe congenital malformations in ruminants and may cause neurological signs in infected horses. Here, SHUV was detected in brain samples of two Israeli cattle, which suffered from severe neurological signs that led to the deaths of the animals. During histopathological examination of the first case, a 5-month-old calf, small perivascular cuffs, composed mainly of neutrophils with few lymphocytes were observed in the brain stem and cerebrum.

Epizootic hemorrhagic disease virus serotype 6 outbreak in Israeli cattle in 2015.

In September 2015, a large outbreak caused by epizootic hemorrhagic disease virus (EHDV) was identified in Israeli dairy and beef farms. The main clinical signs were reduced milk production, weakness, drooling, lameness and recumbency, fever, slight erythema of nasal and oral mucosae, weight loss, and abortion. Dyspnea, cachexia, and death were observed less frequently.

Characterization of Shuni viruses detected in Israel.

Shuni virus (SHUV) was recently identified in Israel in several brains of ovine, bovine, and goat fetuses and newborn animals with congenital arthrogryposis-hydranencephaly syndrome. In the present study, the sequences of several Israeli SHUV strains were analyzed in detail; based on the small genome segment which encodes the nucleocapsid protein and the small nonstructural protein (NSs), a very high similarity of 99-100 % among each other was found. In contrast to the highly conserved N protein, several mutations were found within the NSs-coding sequence of SHUVs present in brain samples of malformed fetuses, resulting in a considerably frequent appearance of stop codons.

Unusual clinical manifestations in Israeli ruminant populations infected with Orbiviruses.

Orbiviruses, some of which are virulent in ruminant species, are transmitted by blood- sucking insects. They can cause the smallest blood vessels to leak, leading to oedema, which is presented as Bluetongue (BT) and/or Epizootic haemorrhagic diseases (EHD). Other clinical manifestations include big-muscle necrosis, excessive scialorrea, and coronitis.

Bluetongue virus serotype 24 (BTV-24) in Israel: phylogenetic characterization and clinical manifestation of the disease.

Bluetongue (BT), an arthropod-borne viral disease of ruminants, a ects sheep most severely than other domestic animals. Bluetongue virus serotype 24 (BTV-24) is one of 26 known Bluetongue virus (BTV) serotypes. In this article, we present data of phylogenetic analysis of 9 viral genes (Seg1, Seg2, Seg3, Seg4, Seg5, Seg6, Seg8, Seg9, and Seg10) from 8 Israeli BTV-24 isolates and relate the genotype of the BTV-24 isolates to their phenotype with regard to clinical manifestations.

Detection and isolation of Bluetongue virus from commercial vaccine batches.

In this report we describe the detection and identification of Bluetongue virus (BTV) contaminations in commercial vaccines. BTV RNA was detected in vaccine batches of Lumpy skin disease (LSD) and Sheep pox (SP) using quantitative PCR (qPCR) for VP1 and NS3 genes. Both batches were positive for VP1 and NS3 in qPCR.

Genetic characterization of HA gene of low pathogenic H9N2 influenza viruses isolated in Israel during 2006-2012 periods.

H9N2 influenza viruses are isolated in Israel since 2000 and became endemic. From November 2006 to the beginning of 2012, many H9N2 viruses were identified, all belonged to the Asian G1-like lineage represented by A/qu/Hong Kong/G1/97 (H9N2). In the present study, 66 isolates were selected for their hemagglutinin gene characterization.

Genetic characterization of H5N1 influenza virus that caused new outbreak in Israel at the beginning of 2008.

Our aim was to characterize the A/ck/Israeli/1055/2008 (H5N1) avian influenza virus that was isolated at the beginning of 2008, and to establish the phylogenetic relationship of this isolate to other H5N1 viruses that were recently isolated in adjacent countries. In light of a study of complete nucleotide sequences of all the genes we found that the isolate (year 2008) was closely related to the H5N1 viruses isolated in Egypt, Israel and Gaza in 2006. The Israeli isolate had the hemagglutinin-connecting peptide with a polybasic amino acid insertion.

Modulation of the severity of highly pathogenic H5N1 influenza in chickens previously inoculated with Israeli H9N2 influenza viruses.

The continued evolution of H9N2 and H5N1 viruses and their spread and re-emergence across Eurasia raise concern that prior H9N2 virus infection may limit the detection of subsequent H5N1 infection in gallinaceous poultry by attenuating the severity of disease. We show that H9N2 viruses isolated from Israeli turkeys during 2000-2004 were antigenically and genetically distinguishable. These three H9N2 viruses caused no overt signs of disease in chickens.