-
The Veterinary Clinics of North... Jul 2024Reemerging and notifiable diseases of cattle and bison continue to pose potential risks to their health and lives and affecting production and the livelihoods of... (Review)
Review
Reemerging and notifiable diseases of cattle and bison continue to pose potential risks to their health and lives and affecting production and the livelihoods of producers. It is essential to understand the clinical presentation of these diseases to watch for possible incursions and infections and to immediately report your suspicions to your State and Federal Animal Health Officials. Three of these reemerging and notifiable diseases of cattle and bison, malignant catarrhal fever, bluetongue virus, and New World screwworm, are presented in this article for increased awareness to consider as a differential if examinations present suggestive clinical signs.
Topics: Animals; Cattle; Communicable Diseases, Emerging; Bluetongue; Cattle Diseases; Bison; Malignant Catarrh; Bluetongue virus
PubMed: 38453550
DOI: 10.1016/j.cvfa.2024.01.007 -
Revue Scientifique Et Technique... Aug 2015African horse sickness (AHS) is a devastating disease of equids caused by an arthropod-borne virus belonging to the Reoviridae family, genus Orbivirus. It is considered... (Review)
Review
African horse sickness (AHS) is a devastating disease of equids caused by an arthropod-borne virus belonging to the Reoviridae family, genus Orbivirus. It is considered a major health threat for horses in endemic areas in sub-Saharan Africa. African horse sickness virus (AHSV) repeatedly caused large epizootics in the Mediterranean region (North Africa and southern Europe in particular) as a result of trade in infected equids. The unexpected emergence of a closely related virus, the bluetongue virus, in northern Europe in 2006 has raised fears about AHSV introduction into Europe, and more specifically into AHSV-free regions that have reported the presence of AHSV vectors, e.g. Culicoides midges. North African and European countries should be prepared to face AHSV incursions in the future, especially since two AHSV serotypes (serotypes 2 and 7) have recently spread northwards to western (e.g. Senegal, Nigeria, Gambia) and eastern Africa (Ethiopia), where historically only serotype 9 had been isolated. The authors review key elements of AHS epidemiology, surveillance and prophylaxis.
Topics: Africa; African Horse Sickness; Animals; Horses; Orbivirus
PubMed: 26601437
DOI: 10.20506/rst.34.2.2359 -
The Veterinary Record Dec 2023
Topics: Sheep; Animals; Bluetongue; Serogroup; Bluetongue virus; Sheep Diseases
PubMed: 38038316
DOI: 10.1002/vetr.3759 -
Acta Virologica Dec 2015Bluetongue (BT) is an insect borne (Culicoides) viral disease of small ruminants in India. While seroprevalence for BT is observed mostly in domestic and wild ruminant... (Review)
Review
Bluetongue (BT) is an insect borne (Culicoides) viral disease of small ruminants in India. While seroprevalence for BT is observed mostly in domestic and wild ruminant animals, the clinical form of disease and severe mortality is observed in sheep. Since the first report of BT in 1960s the country became endemic for the disease and most of the BT virus (BTV) serotypes (22 out of 27 worldwide) have been reported. The genome sequence analyses of these viruses revealed that both the eastern and western topotypes as well as their reassortant strains are present in India. It further revealed that some of these viruses are very close to live vaccines used in other countries. The severe economic concern justifies the need to develop sensitive and reliable diagnostic tests for BT. The virus isolation followed by identification by electron microscopy is gold standard test, but it is time consuming and not easily available in all the laboratories. Therefore, nucleic acid-based rapid diagnostic tests such as PCR, real-time PCR etc. are used nowadays. The BT control program in India includes vector control as well as effective vaccination. The vector population is controlled by vector traps, synthetic pesticides and some of the herbal compounds. For effective vaccination, the serotypes prevalent in a particular geographical area must be known, which can be achieved by continuous monitoring and sero-surveillance of disease. The multivalent inactivated vaccines are more suitable for India in comparison to modified live vaccines as the latter may turn to virulent and may lead to severe outbreak of the disease.
Topics: Animals; Bluetongue; Bluetongue virus; Ceratopogonidae; India; Insect Vectors
PubMed: 26666181
DOI: 10.4149/av_2015_04_317 -
Revue Scientifique Et Technique... Aug 2015Summary Epizootic haemorrhagic disease (EHD) is an arthropod-transmitted viral disease of certain wild ungulates, notably North American white-tailed deer and, more... (Review)
Review
Summary Epizootic haemorrhagic disease (EHD) is an arthropod-transmitted viral disease of certain wild ungulates, notably North American white-tailed deer and, more rarely, cattle. The disease in white-tailed deer results from vascular injury analogous to that caused by bluetongue virus (BTV), to which EHD virus (EHDV) is closely related. There are seven serotypes of EHDV recognised, and Ibaraki virus, which is the cause of sporadic disease outbreaks in cattle in Asia, is included in EHDV serotype 2. The global distribution and epidemiology of BTV and EHDV infections are also similar, as both viruses occur throughout temperate and tropical regions of the world where they are transmitted by biting Culicoides midges and infect a wide variety of domestic and wild ungulates. However, the global distribution and epidemiology of EHDV infection are less well characterised than they are for BTV. Whereas most natural and experimental EHDV infections (other than Ibaraki virus infection) of livestock are subclinical or asymptomatic, outbreaks of EHD have recently been reported among cattle in the Mediterranean Basin, Reunion Island, South Africa, and the United States. Accurate and convenient laboratory tests are increasingly available for the sensitive and specific serological and virological diagnosis of EHDV infection and confirmation of EHD in animals, but commercial vaccines are available only for prevention of Ibaraki disease and not for protection against other strains and serotypes of EHDV.
Topics: Animals; Cattle; Disease Outbreaks; Hemorrhagic Disease Virus, Epizootic; Reoviridae Infections
PubMed: 26601439
DOI: 10.20506/rst.34.2.2361 -
Advances in Virus Research 2020Bluetongue virus (BTV) is an insect-vectored emerging pathogen of wild ruminants and livestock in many parts of the world. The virion particle is a complex structure of... (Review)
Review
Bluetongue virus (BTV) is an insect-vectored emerging pathogen of wild ruminants and livestock in many parts of the world. The virion particle is a complex structure of consecutive layers of protein surrounding a genome of 10 double-stranded (ds) RNA segments. BTV has been studied extensively as a model system for large, nonenveloped dsRNA viruses. A combination of recombinant proteins and particles together with reverse genetics, high-resolution structural analysis by X-ray crystallography and cryo-electron microscopy techniques have been utilized to provide an order for the assembly of the capsid shell and the protein sequestration required for it. Further, a reconstituted in vitro assembly system and RNA-RNA interaction assay, have defined the individual steps required for the assembly and packaging of the 10-segmented RNA genome. In addition, various microscopic techniques have been utilized to illuminate the stages of virus maturation and its egress via multiple pathways. These findings have not only given an overall understanding of BTV assembly and morphogenesis but also indicated that similar assembly and egress pathways are likely to be used by related viruses and provided an informed starting point for intervention or prevention.
Topics: Animals; Bluetongue virus; Books; Capsid; Capsid Proteins; Cryoelectron Microscopy; Genome, Viral; Insect Vectors; Livestock; Viral Proteins; Virion; Virus Assembly; Virus Release; Virus Replication
PubMed: 33837718
DOI: 10.1016/bs.aivir.2020.08.002 -
Current Opinion in Virology Jun 2017Bluetongue virus (BTV) is an insect-vectored emerging pathogen of wild ruminants and livestock in many parts of the world. The virion particle is a complex structure of... (Review)
Review
Bluetongue virus (BTV) is an insect-vectored emerging pathogen of wild ruminants and livestock in many parts of the world. The virion particle is a complex structure of consecutive layers of protein surrounding a genome of ten double-stranded (ds) RNA segments. BTV has been studied as a model system for large, non-enveloped dsRNA viruses. Several new techniques have been applied to define the virus-encoded enzymes required for RNA replication to provide an order for the assembly of the capsid shell and the protein sequestration required for it. Further, a reconstituted in vitro system has defined the individual steps of the assembly and packaging of the genomic RNA. These findings illuminate BTV assembly and indicate the pathways that related viruses might use to provide an informed starting point for intervention or prevention.
Topics: Animals; Bluetongue virus; Genome, Viral; Humans; RNA, Viral; Viral Structures; Virion; Virus Assembly; Virus Replication
PubMed: 28609677
DOI: 10.1016/j.coviro.2017.05.003 -
Transboundary and Emerging Diseases Apr 2016Bluetongue (BT) is an insectborne endemic disease in India. Although infections are observed in domestic and wild ruminants, the clinical disease and mortality are... (Review)
Review
Bluetongue (BT) is an insectborne endemic disease in India. Although infections are observed in domestic and wild ruminants, the clinical disease and mortality are observed only in sheep, especially in the southern states of the country. The difference in disease patterns in different parts of the country could be due to varied climatic conditions, sheep population density and susceptibility of the sheep breeds to BT. Over the five decades after the first report of BT in 1964, most of the known serotypes of bluetongue virus (BTV) have been reported from India either by virus isolation or by detection of serotype-specific antibodies. There have been no structured longitudinal studies to identify the circulating serotypes throughout the country. At least ten serotypes were isolated between 1967 and 2000 (BTV-1-4, 6, 9, 16-18, 23). Since 2001, the All-India Network Programme on Bluetongue and other laboratories have isolated eight different serotypes (BTV-1-3, 9, 10, 12, 16, 21). Genetic analysis of these viruses has revealed that some of them vary substantially from reference viruses, and some show high sequence identity with modified live virus vaccines used in different parts of the world. These observations have highlighted the need to develop diagnostic capabilities, especially as BT outbreaks are still declared based on clinical signs. Although virus isolation and serotyping are the gold standards, rapid methods based on the detection of viral nucleic acid may be more suitable for India. The epidemiological investigations also have implications for vaccine design. Although only a handful serotypes may be involved in causing outbreaks every year, the combination of serotypes may change from year to year. For effective control of BT in India, it may be pertinent to introduce sentinel and vector traps systems for identification of the circulating serotypes and to evaluate herd immunity against different serotypes, so that relevant strains can be included in vaccine formulations.
Topics: Animals; Bluetongue; Bluetongue virus; DNA, Viral; India; Prevalence; Serogroup; Serotyping; Sheep; Viral Vaccines
PubMed: 25164573
DOI: 10.1111/tbed.12258 -
Viruses Mar 2019While serological and virological evidence documents the exposure of bats to medically-important arboviruses, their role as reservoirs or amplifying hosts is less...
While serological and virological evidence documents the exposure of bats to medically-important arboviruses, their role as reservoirs or amplifying hosts is less well-characterized. We describe a novel orbivirus () isolated from an Egyptian fruit bat () trapped in 2013 in Uganda and named Bukakata orbivirus. This is the fifth orbivirus isolated from a bat, however genetic information had previously only been available for one bat-associated orbivirus. We performed whole-genome sequencing on Bukakata orbivirus and three other bat-associated orbiviruses (Fomede, Ife, and Japanaut) to assess their phylogenetic relationship within the genus and develop hypotheses regarding potential arthropod vectors. Replication kinetics were assessed for Bukakata orbivirus in three different vertebrate cell lines. Lastly, qRT-PCR and nested PCR were used to determine the prevalence of Bukakata orbivirus RNA in archived samples from three populations of Egyptian fruit bats and one population of cave-associated soft ticks in Uganda. Complete coding sequences were obtained for all ten segments of Fomede, Ife, and Japanaut orbiviruses and for nine of the ten segments for Bukakata orbivirus. Phylogenetic analysis placed Bukakata and Fomede in the tick-borne orbivirus clade and Ife and Japanaut within the /phlebotomine sandfly orbivirus clade. Further, Bukakata and Fomede appear to be serotypes of the species. Bukakata orbivirus replicated to high titers (10⁶⁻10⁷ PFU/mL) in Vero, BHK-21 [C-13], and R06E (Egyptian fruit bat) cells. Preliminary screening of archived bat and tick samples do not support Bukakata orbivirus presence in these collections, however additional testing is warranted given the phylogenetic associations observed. This study provided complete coding sequence for several bat-associated orbiviruses and in vitro characterization of a bat-associated orbivirus. Our results indicate that bats may play an important role in the epidemiology of viruses in the genus and further investigation is warranted into vector-host associations and ongoing surveillance efforts.
Topics: Animals; Cell Line; Chiroptera; Chlorocebus aethiops; Disease Reservoirs; Genome, Viral; Open Reading Frames; Orbivirus; Phylogeny; RNA, Viral; Real-Time Polymerase Chain Reaction; Sequence Analysis, DNA; Vero Cells; Viral Proteins; Virus Replication; Whole Genome Sequencing
PubMed: 30832334
DOI: 10.3390/v11030209 -
Journal of Infection in Developing... Feb 2023Bluetongue (BT), once considered a disease of sheep confined to the southern African region, has spread all over the world. BT is a viral disease caused by the... (Review)
Review
Bluetongue (BT), once considered a disease of sheep confined to the southern African region, has spread all over the world. BT is a viral disease caused by the bluetongue virus (BTV). BT is regarded as an economically important disease in ruminants of compulsory notification to OIE. BTV is transmitted by the bite of Culicoides species. Research over the years has led to a better understanding of the disease, the nature of the virus life cycle between ruminants and Culicoides species, and its distribution in different geographical regions. Advances have also been made in understanding the molecular structure and function of the virus, the biology of the Culicoides species, its ability to transmit the disease, and the persistence of the virus inside the Culicoides and the mammalian hosts. Global climate change has enabled the colonization of new habitats and the spread of the virus into additional species of the Culicoides vector. This review highlights some of the current findings on the status of BT in the world based on the latest research on disease aspects, virus-host-vector interactions, and the different diagnostic approaches and control strategies available for BTV.
Topics: Animals; Sheep; Bluetongue virus; Insect Vectors; Ruminants; Bluetongue; Ceratopogonidae
PubMed: 36897898
DOI: 10.3855/jidc.16947