First Isolation and Molecular Characterization of Umatilla Virus (Sedoreoviridae, Orbivirus) in Brazil.

In this study, we provide a genomic description of the first isolation of the Umattila virus (UMAV) in Brazil. The virus was obtained from the blood of a bird (Turdus fumigatus) and isolated in a C6/36 cell culture. The viral genome contains ten segments, and its organization is characteristic of viruses of the genus Orbivirus (family Sedoreoviridae). The coding region of each segment was sequenced, demonstrating the nucleotide identity with UMAV. The phylogenetic inference results were in line with these findings and demonstrated the formation of two distinct monophyletic clades containing strains isolated around the world, where our isolate, belonging to the same clade as the prototype strain, was allocated to a different subclade, highlighting the genetic divergence between them. This work reports the first isolation of UMAV in Brazil, and due to the scarcity of information on this viral agent in the scientific literature, it is essential to carry out further studies to better understand its epidemiology, dispersion, and, in particular, its interactions with vertebrate hosts, vectors, and the environment.

The Study of Bluetongue Virus (BTV) and Epizootic Hemorrhagic Disease Virus (EHDV) Circulation and Vectors at the Municipal Parks and Zoobotanical Foundation of Belo Horizonte, Minas Gerais, Brazil (FPMZB-BH).

Bluetongue Virus (BTV) and Epizootic Hemorrhagic Disease Virus (EHDV) are Orbiviruses primarily transmitted by their biological vector, Culicoides spp. Latreille, 1809 (Diptera: Ceratopogonidae). These viruses can infect a diverse range of vertebrate hosts, leading to disease outbreaks in domestic and wild ruminants worldwide. This study, conducted at the Belo Horizonte Municipal Parks and Zoobotany Foundation (FPMZB-BH), Minas Gerais, Brazil, focused on Orbivirus and its vectors. Collections of Culicoides spp. were carried out at the FPMZB-BH from 9 December 2021 to 18 November 2022. A higher prevalence of these insects was observed during the summer months, especially in February. Factors such as elevated temperatures, high humidity, fecal accumulation, and proximity to large animals, like camels and elephants, were associated with increased Culicoides capture. Among the identified Culicoides spp. species, Culicoides insignis Lutz, 1913, constituted 75%, and Culicoides pusillus Lutz, 1913, 6% of the collected midges, both described as competent vectors for Orbivirus transmission. Additionally, a previously unreported species in Minas Gerais, Culicoides debilipalpis Lutz, 1913, was identified, also suspected of being a transmitter of these Orbiviruses. The feeding preferences of some Culicoides species were analyzed, revealing that C. insignis feeds on deer, Red deer (Cervus elaphus) and European fallow deer (Dama dama). Different Culicoides spp. were also identified feeding on humans, raising concerns about the potential transmission of arboviruses at the site. In parallel, 72 serum samples from 14 susceptible species, including various Cervids, collected between 2012 and 2022 from the FPMZB-BH serum bank, underwent Agar Gel Immunodiffusion (AGID) testing for BTV and EHDV. The results showed 75% seropositivity for BTV and 19% for EHDV. Post-testing analysis revealed variations in antibody presence against BTV in a tapir and a fallow deer and against EHDV in a gemsbok across different years. These studies confirm the presence of BTV and EHDV vectors, along with potential virus circulation in the zoo. Consequently, implementing control measures is essential to prevent susceptible species from becoming infected and developing clinical diseases.

Blue tongue virus in dairy cattle in the Southern region of Minas Gerais, Brazil - serological survey

Background: Blue tongue (BT) is a noncontagious viral disease transmitted by hematophagous arthropods, especially of the genus Culicoides. The economic impact of the disease is related not only to deaths in sheep herds but also to the possible correlation of virus infection with the development of other diseases, such as pneumonia, abortion and movement problems. The economic losses caused by Blue Tongue are linked to restrictions on the import and export of animals and their genetic material and to the reproductive disorders associated with this disease. In addition, the fact that cattle take the role of reservoir, combined with the care by other countries with outbreaks of infection and biological contamination of their products, hinders trade in Mercosul, United States and Europe. Cattle are affected by Blue Tongue Virus in endemic areas and in some epidemic areas, but the development of clinical disease is rare. The clinical signs, when evident, range from reproductive losses, such as embryonic death, abortion, fetal malformation, temporary sterility, infertility in bulls, stillbirths and the birth of weak animals. The objective of this study was to determine the epidemiological aspects of Blue Tongue Virus (BTV) infection in dairy cattle in the Lavras region, state of Minas Gerais, Brazil. Materials, Methods & Results: A cross-sectional study was conducted to evaluate the frequency of cattle and herds seropositive for Blue Tongue in the southern region of Minas Gerais. In this study, 54 dairy farms were visited. A total of 586 serum samples were collected from cows of reproductive age. Sampling was random, and serum samples were collected from lactating cows over 24 months of age by puncture of the jugular vein and/or coccidian vein. The samples were transported and stored at the Setor de Patologia Veterinária, at the Universidade Federal de Lavras (SPV-UFLA), where they were centrifuged, and the serum aliquots were obtained, transferred to microtubes and kept at -20°C until the serological tests were performed. The samples were tested with the agarose gel immunodiffusion test (AGID) for anti-blue tongue virus antibodies. The AGID test is more practical and is the main method used to identify Blue Tongue Virus seroprevalence in different ruminant species. They are considered important tools for epidemiological surveillance of the disease. A prevalence of 83.28% was observed among animals that were seropositive for Blue Tongue Virus (488/586; IC 95% = 80.0 - 86.21). In addition, 100% (54/54; IC 95% = 93.4 - 100.0) of the farms had at least 1 positive animal, with rates ranging from 45.45% to 100% within the herds and where 22.22% of the farms had rates of 100% of the animals being positive. Discussion: Blue Tongue is a disease known to affect domestic and wild ruminants in Brazil. However, there is a lack of more precise information about its epidemiology and occurrence in the country and of joint efforts of researchers, producers and the government to understand in detail both the biology of vectors and the viral biology of Blue Tongue Virus in Brazil. This is the first record of detection of anti-blue tongue virus antibodies in cattle in the southern region of Minas Gerais. The results suggest that Blue Tongue Virus is present in cattle in the study area.

Detection of bluetongue virus antibodies in sheep from Paraná, Brazil / Detecção de anticorpos para o vírus da língua azul em ovinos do estado do Paraná, Brasil

Bluetongue (BT) is an infectious and non-contagious disease caused by bluetongue virus (BTV) belonging to the genus Orbivirus. It is transmitted by a hematophagous vector, Culicoides sp., to ruminants, particularly to sheep, which are most susceptible to this disease. The main serological tests are agar gel immunodiffusion (AGID), which is recommended by the World Organization for Animal Health (OIE), and the competitive enzyme-linked immunosorbent assay (cELISA), which has the advantage of no cross-reaction with other orbiviruses. The aim was to compare the results of these two tests by conducting them on sera collected from sheep in the state of Paraná, Brazil. From March to October 2017, serum samples were collected from 270 sheep from 10 farms in six mesoregions of Paraná. The samples were subjected to AGID and cELISA to detect antibodies against BTV. Based on the test results, we classified the sheep as low, moderate, and high occurrence. The results demonstrated that 64.81% (175/270) of the sheep were seropositive through the cELISA test, showing a high occurrence, and 41.11% (111/270) were seropositive through the AGID test, indicating a moderate occurrence. The concordance between the tests was moderate (0.51) as determined by the Kappa coefficient. Among the studied farms, 90% (9/10) presented at least one seropositive sheep, and the number of animals tested positive by the cELISA test was higher than those by the AGID test. Favorable climate, which favors the presence and multiplication of the culicoid vector and the occurrence of infection, was the biggest predominant factor responsible for the obtained results. The low occurrence in farms with milder climate suggest that the presence of antibodies also occurs due to the low pathogenicity of circulating serotypes in the different mesoregions studied. It is concluded that BTV infection is present in the sheep herds in Paraná, and the occurrence...(AU)

A língua azul (LA) é uma enfermidade infecciosa e não contagiosa causada por um vírus (VLA) do gênero Orbivirus, transmitida por vetores hematófagos Culicoides sp., aos ruminantes sobretudo aos ovinos, espécie mais susceptível. Os principais testes sorológicos utilizados são a Imunodifusão em Gél de Ágar (IDGA), preconizada pela OIE, e o teste Imunoensaio Enzimático Competitivo (ELISAc), sendo que este tem como vantagem não ocorrer reação cruzada contra outros orbivírus. O objetivo do trabalho foi detectar a presença de anticorpos contra o VLA em ovinos no estado do Paraná através dos testes diagnósticos IDGA e ELISAc. Durante os meses de março a outubro de 2017, colheu-se sangue de 270 ovinos, em 10 propriedades localizadas em seis mesorregiões paranaenses. As amostras foram submetidas aos testes de IDGA e ELISAc para detecção de anticorpos contra o VLA. Baseado nos resultados classificaram-se os rebanhos como baixa, moderada ou elevada ocorrência. Os resultados demonstraram elevada ocorrência através do teste de ELISAc, que apresentou 64,81% (175/270) de ovinos positivos, e moderada ocorrência através do IDGA, com 41,11% (111/270) de ovinos soropositivos. A concordância obtida entre os testes foi moderada (0,51) através do coeficiente Kappa. O número de ovinos reagentes no exame de ELISAc foi maior que o teste de IDGA em todas as propriedades positivas, demonstrando ser superior. O clima propício foi um dos fatores favoráveis para as ocorrências observadas, pois favorece a presença e multiplicação do vetor Culicoide e a ocorrência da infecção. A baixa ocorrência nas propriedades com clima mais ameno sugere que a presença de anticorpos provavelmente ocorra também pela baixa patogenicidade dos sorotipos circulantes nas diferentes mesorregiões estudadas. Conclui-se que há infecção de VLA no rebanho ovino paranaense, e a detecção de anticorpos para o VLA foi moderada, através do teste de IDGA, e elevada, através do teste ELISAc.(AU)

Detection of bluetongue virus antibodies in sheep from Paraná, Brazil / Detecção de anticorpos para o vírus da língua azul em ovinos do estado do Paraná, Brasil

Bluetongue (BT) is an infectious and non-contagious disease caused by bluetongue virus (BTV) belonging to the genus Orbivirus. It is transmitted by a hematophagous vector, Culicoides sp., to ruminants, particularly to sheep, which are most susceptible to this disease. The main serological tests are agar gel immunodiffusion (AGID), which is recommended by the World Organization for Animal Health (OIE), and the competitive enzyme-linked immunosorbent assay (cELISA), which has the advantage of no cross-reaction with other orbiviruses. The aim was to compare the results of these two tests by conducting them on sera collected from sheep in the state of Paraná, Brazil. From March to October 2017, serum samples were collected from 270 sheep from 10 farms in six mesoregions of Paraná. The samples were subjected to AGID and cELISA to detect antibodies against BTV. Based on the test results, we classified the sheep as low, moderate, and high occurrence. The results demonstrated that 64.81% (175/270) of the sheep were seropositive through the cELISA test, showing a high occurrence, and 41.11% (111/270) were seropositive through the AGID test, indicating a moderate occurrence. The concordance between the tests was moderate (0.51) as determined by the Kappa coefficient. Among the studied farms, 90% (9/10) presented at least one seropositive sheep, and the number of animals tested positive by the cELISA test was higher than those by the AGID test. Favorable climate, which favors the presence and multiplication of the culicoid vector and the occurrence of infection, was the biggest predominant factor responsible for the obtained results. The low occurrence in farms with milder climate suggest that the presence of antibodies also occurs due to the low pathogenicity of circulating serotypes in the different mesoregions studied. It is concluded that BTV infection is present in the sheep herds in Paraná, and the occurrence...

A língua azul (LA) é uma enfermidade infecciosa e não contagiosa causada por um vírus (VLA) do gênero Orbivirus, transmitida por vetores hematófagos Culicoides sp., aos ruminantes sobretudo aos ovinos, espécie mais susceptível. Os principais testes sorológicos utilizados são a Imunodifusão em Gél de Ágar (IDGA), preconizada pela OIE, e o teste Imunoensaio Enzimático Competitivo (ELISAc), sendo que este tem como vantagem não ocorrer reação cruzada contra outros orbivírus. O objetivo do trabalho foi detectar a presença de anticorpos contra o VLA em ovinos no estado do Paraná através dos testes diagnósticos IDGA e ELISAc. Durante os meses de março a outubro de 2017, colheu-se sangue de 270 ovinos, em 10 propriedades localizadas em seis mesorregiões paranaenses. As amostras foram submetidas aos testes de IDGA e ELISAc para detecção de anticorpos contra o VLA. Baseado nos resultados classificaram-se os rebanhos como baixa, moderada ou elevada ocorrência. Os resultados demonstraram elevada ocorrência através do teste de ELISAc, que apresentou 64,81% (175/270) de ovinos positivos, e moderada ocorrência através do IDGA, com 41,11% (111/270) de ovinos soropositivos. A concordância obtida entre os testes foi moderada (0,51) através do coeficiente Kappa. O número de ovinos reagentes no exame de ELISAc foi maior que o teste de IDGA em todas as propriedades positivas, demonstrando ser superior. O clima propício foi um dos fatores favoráveis para as ocorrências observadas, pois favorece a presença e multiplicação do vetor Culicoide e a ocorrência da infecção. A baixa ocorrência nas propriedades com clima mais ameno sugere que a presença de anticorpos provavelmente ocorra também pela baixa patogenicidade dos sorotipos circulantes nas diferentes mesorregiões estudadas. Conclui-se que há infecção de VLA no rebanho ovino paranaense, e a detecção de anticorpos para o VLA foi moderada, através do teste de IDGA, e elevada, através do teste ELISAc.

Genomic characterization of Changuinola viruses from Panama: evidence for multiple genome segment reassortment.

The complete coding sequences of five divergent strains of Changuinola virus (CGLV), collected over a 16-year period in Panama, were determined, using viral metagenomics. Each strain had 10 RNA segments that encoded structural and non-structural proteins with amino acid identities ranging from 33 to 99% with sequences of other 15 members of the Changuinola virus (Reoviridae: Orbivirus) species group. Genetic analyses of the five Panamanian virus strains revealed probable reassortment among multiple segments of the viruses.

Serological survey of bluetongue virus in sheep from Minas Gerais / Inquérito sorológico do vírus da língua azul em ovinos de Minas Gerais

Bluetongue is an infectious, non-contagious disease that affects domestic and wild ruminants, caused by a virus from the Orbivirus genus, Reoviridae family, transmitted by arthropod vectors of the Culicoides genus. This paper aims to be the first serological survey of bluetongue in sheep from the Meso-regions of Campo das Vertentes and South and Southeast of Minas Gerais. Samples were collected from sheep from different properties. The serum samples were submitted to Agar Gel Immunodiffusion (AGID) and competitive Enzyme-Linked Immunosorbent Assay (cELISA). 303 serum samples were submitted to AGID and cELISA. In these samples, 164 (54.13%) were positive in the AGID technique, and 171 (56.44%) positive in the cELISA technique, with an almost perfect agreement between the techniques (kappa index = 0.887). In all visited properties, positive animals have been found in the herd. Animals acquired from properties of the studied mesoregions were more likely to be positive in IDGA and cELISA tests than animals acquired from properties in other regions of Brazil (p<0.001). These results suggest that bluetongue virus (BTV) is widespread in the mesoregions of Campo das Vertentes and South and Southeast of Minas Gerais.(AU)

A língua azul (LA) é uma doença infecciosa, não contagiosa, que acomete ruminantes domésticos e silvestres, causada por um vírus do gênero Orbivirus da família Reoviridae, transmitida por vetores artrópodes do gênero Culicoides. O presente estudo representa o primeiro trabalho a realizar um inquérito sorológico da língua azul em rebanhos ovinos nas Mesorregiões de Campo das Vertentes e Sul e Sudoeste de Minas Gerais. Foram coletadas amostras de soro de ovinos de diferentes propriedades. As amostras de soro foram submetidas aos testes de imunodifusão em gel de ágar (IDGA) e ensaio de imunoadsorção enzimática por competição (cELISA). Ao todo 303 amostras de soro foram submetidas ao IDGA e cELISA. Dessas amostras, 164 (54,13%) foram positivas na técnica de IDGA e 171 (56,44%) positivas na técnica de cELISA, havendo concordância quase perfeita entre as técnicas (índice kappa = 0,887). Em todas as propriedades visitadas, foram encontrados animais positivos no rebanho. Animais adquiridos de propriedades das Mesorregiões estudadas, tiveram mais chances de serem positivos nos testes de IDGA e cELISA do que animais adquiridos de propriedades de outras Regiões do Brasil (p<0,001). Esses resultados sugerem que o vírus da língua azul encontra-se disseminado em ovinos nas Mesorregiões de Campo das Vertentes e Sul e Sudoeste de Minas Gerais.(AU)

Serological survey of bluetongue virus in sheep from Minas Gerais / Inquérito sorológico do vírus da língua azul em ovinos de Minas Gerais

Bluetongue is an infectious, non-contagious disease that affects domestic and wild ruminants, caused by a virus from the Orbivirus genus, Reoviridae family, transmitted by arthropod vectors of the Culicoides genus. This paper aims to be the first serological survey of bluetongue in sheep from the Meso-regions of Campo das Vertentes and South and Southeast of Minas Gerais. Samples were collected from sheep from different properties. The serum samples were submitted to Agar Gel Immunodiffusion (AGID) and competitive Enzyme-Linked Immunosorbent Assay (cELISA). 303 serum samples were submitted to AGID and cELISA. In these samples, 164 (54.13%) were positive in the AGID technique, and 171 (56.44%) positive in the cELISA technique, with an almost perfect agreement between the techniques (kappa index = 0.887). In all visited properties, positive animals have been found in the herd. Animals acquired from properties of the studied mesoregions were more likely to be positive in IDGA and cELISA tests than animals acquired from properties in other regions of Brazil (p<0.001). These results suggest that bluetongue virus (BTV) is widespread in the mesoregions of Campo das Vertentes and South and Southeast of Minas Gerais.(AU)

A língua azul (LA) é uma doença infecciosa, não contagiosa, que acomete ruminantes domésticos e silvestres, causada por um vírus do gênero Orbivirus da família Reoviridae, transmitida por vetores artrópodes do gênero Culicoides. O presente estudo representa o primeiro trabalho a realizar um inquérito sorológico da língua azul em rebanhos ovinos nas Mesorregiões de Campo das Vertentes e Sul e Sudoeste de Minas Gerais. Foram coletadas amostras de soro de ovinos de diferentes propriedades. As amostras de soro foram submetidas aos testes de imunodifusão em gel de ágar (IDGA) e ensaio de imunoadsorção enzimática por competição (cELISA). Ao todo 303 amostras de soro foram submetidas ao IDGA e cELISA. Dessas amostras, 164 (54,13%) foram positivas na técnica de IDGA e 171 (56,44%) positivas na técnica de cELISA, havendo concordância quase perfeita entre as técnicas (índice kappa = 0,887). Em todas as propriedades visitadas, foram encontrados animais positivos no rebanho. Animais adquiridos de propriedades das Mesorregiões estudadas, tiveram mais chances de serem positivos nos testes de IDGA e cELISA do que animais adquiridos de propriedades de outras Regiões do Brasil (p<0,001). Esses resultados sugerem que o vírus da língua azul encontra-se disseminado em ovinos nas Mesorregiões de Campo das Vertentes e Sul e Sudoeste de Minas Gerais.(AU)

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

Equine encephalosis (EE) is an acute, arthropod-borne, noncontagious, febrile disease of equids. The clinical signs of EE are similar to milder forms of African horse sickness (AHS) and the two diseases can be easily confused. The Equine encephalosis virus (EEV) is a distinct virus species within the genus Orbivirus, family Reoviridae, with ten linear segments of dsRNA genome. Seven distinct serotypes of EEV have been recognised on the basis of sequence analyses of Seg-2. The need for differential diagnosis of similar forms of EE and AHS warranted the development of molecular diagnostic methods for specific detection and identification of EEV. We report the development of quantitative real-time RT-PCR assay for detection of any member of the EEV species targeting the highly conserved EEV Seg-9. Similar serotype-specific qRT-PCR assays were designed for each of the seven EEV serotypes targeting genome Seg-2, encoding the serotype determining VP2 protein. These assays were evaluated using different EEV serotypes and other closely related orbiviruses. They were shown to be EEV virus species-specific, or EEV type-specific capable of detecting 1 to 13 copies of viral RNA in clinical samples. The assays failed to detect RNA from closely related orbiviruses, including AHSV and Peruvian horse sickness virus (PHSV) isolates.

Bluetongue disease in sheep: a review / O vírus da língua azul em ovinos: uma revisão

The present review aims to show the main aspects related to bluetongue virus (BTV) infection in sheep. The bluetongue (BT) is a viral, infectious, and non-contagious disease caused by a virus (BTV) of the Orbivirus genus, transmited by a hematophagous vector of the Culicoides genus, to domestic and wild ruminants, mainly to sheep, the most susceptible species. It is caused by the association of endemic with climate conditions, with high temperatures and humidity. Economic loss is directly linked to death, abortion, weight loss, loss of milk, and meat production, and, indirectly, to the restriction on the export of animals and their by-products. The study concludes that the BTV is worldwidely spread, and probably persists due to the warm and humid climate that leads to the proliferation of Culicoides sp., being necessary to adopt measures that reduce the risk factors associated to the BTV infection.(AU)

A presente revisão objetivou apresentar os principais aspectos relacionados à infecção causada pelo vírus da língua azul em ovinos. A língua azul é uma doença viral, infecciosa e não contagiosa, causada por um vírus (BTV) do gênero Orbivírus, transmitida por meio de vetores hematófagos do gênero Culicoides a ruminantes domésticos e selvagens, principalmente aos ovinos, a espécie mais susceptível. A infecção ocorre de forma endêmica, associada a condições climáticas com elevada temperatura e umidade. As perdas econômicas estão ligadas diretamente à morte, ao abortamento, à perda de peso, à perda na produção de leite e carne, e, indiretamente, devido à restrição na exportação de animais e seus subprodutos. O estudo conclui que a língua azul está disseminada mundialmente e persiste, provavelmente, devido ao clima quente e úmido que propicia a proliferação de Culicoides sp., sendo necessário adotar medidas que diminuam os fatores de risco associados à infecção pelo vírus.(AU)

Bluetongue disease in sheep: a review / O vírus da língua azul em ovinos: uma revisão

The present review aims to show the main aspects related to bluetongue virus (BTV) infection in sheep. The bluetongue (BT) is a viral, infectious, and non-contagious disease caused by a virus (BTV) of the Orbivirus genus, transmited by a hematophagous vector of the Culicoides genus, to domestic and wild ruminants, mainly to sheep, the most susceptible species. It is caused by the association of endemic with climate conditions, with high temperatures and humidity. Economic loss is directly linked to death, abortion, weight loss, loss of milk, and meat production, and, indirectly, to the restriction on the export of animals and their by-products. The study concludes that the BTV is worldwidely spread, and probably persists due to the warm and humid climate that leads to the proliferation of Culicoides sp., being necessary to adopt measures that reduce the risk factors associated to the BTV infection.(AU)

A presente revisão objetivou apresentar os principais aspectos relacionados à infecção causada pelo vírus da língua azul em ovinos. A língua azul é uma doença viral, infecciosa e não contagiosa, causada por um vírus (BTV) do gênero Orbivírus, transmitida por meio de vetores hematófagos do gênero Culicoides a ruminantes domésticos e selvagens, principalmente aos ovinos, a espécie mais susceptível. A infecção ocorre de forma endêmica, associada a condições climáticas com elevada temperatura e umidade. As perdas econômicas estão ligadas diretamente à morte, ao abortamento, à perda de peso, à perda na produção de leite e carne, e, indiretamente, devido à restrição na exportação de animais e seus subprodutos. O estudo conclui que a língua azul está disseminada mundialmente e persiste, provavelmente, devido ao clima quente e úmido que propicia a proliferação de Culicoides sp., sendo necessário adotar medidas que diminuam os fatores de risco associados à infecção pelo vírus.(AU)

Bluetongue in white-tailed deer (Odocoileus virginianus) in Northeastern Mexico

Bluetongue (BT) and epizootic hemorrhagic disease of deer (EHD) are two distinct viral hemorrhagic diseases of domestic and wildruminants caused by members of the family Reoviridae and transmitted by Culicoides midges. These conditions have been recognized in Canada and the United States for many years, but not in Mexico. Although in Mexico there is serologic evidence of EHD virus (EHDV) and bluetongue virus (BTV) in domestic and wild ruminants, to our knowledge, there have never been reports of clinical illness or fatalities attributed to either of these viruses. Two free ranging white-tailed deer (Odocoileus virginianus) in twolicensed hunting ranches in Northern Mexico near the Texas border died unexpectedly. Postmortem and microscopic examinations revealed hemorrhagic lesions compatible with viral hemorrhagic disease (Reoviridae: Orbivirus). Tissues from one animal tested positive by RT-PCR for BTV but negative for EHDV. To our knowledge, this is the first time in Mexico where deer dying with hemorrhagic lesions consistent with Bluetongue tested positive for BTV by PCR.(AU)

Bluetongue in white-tailed deer (Odocoileus virginianus) in Northeastern Mexico

Bluetongue (BT) and epizootic hemorrhagic disease of deer (EHD) are two distinct viral hemorrhagic diseases of domestic and wildruminants caused by members of the family Reoviridae and transmitted by Culicoides midges. These conditions have been recognized in Canada and the United States for many years, but not in Mexico. Although in Mexico there is serologic evidence of EHD virus (EHDV) and bluetongue virus (BTV) in domestic and wild ruminants, to our knowledge, there have never been reports of clinical illness or fatalities attributed to either of these viruses. Two free ranging white-tailed deer (Odocoileus virginianus) in twolicensed hunting ranches in Northern Mexico near the Texas border died unexpectedly. Postmortem and microscopic examinations revealed hemorrhagic lesions compatible with viral hemorrhagic disease (Reoviridae: Orbivirus). Tissues from one animal tested positive by RT-PCR for BTV but negative for EHDV. To our knowledge, this is the first time in Mexico where deer dying with hemorrhagic lesions consistent with Bluetongue tested positive for BTV by PCR.

Association of vectors and environmental conditions during the emergence of Peruvian horse sickness orbivirus and Yunnan orbivirus in northern Peru.

Since 1983, cases of diseased donkeys and horses with symptoms similar to those produced by alphaviruses were identified in two departments in northern Peru; however serological testing ruled out the presence of those viruses and attempts to isolate an agent were also unproductive. In 1997, also in northern Peru, two new orbiviruses were discovered, each recognized as a causative agent of neurological diseases in livestock and domestic animals and, at the same time, mosquitoes were found to be infected with these viruses. Peruvian horse sickness virus (PHSV) was isolated from pools of culicid mosquitoes, Aedes serratus and Psorophora ferox, and Yunnan virus (YUOV) was isolated from Aedes scapularis in the subtropical jungle (upper jungle) located on the slope between the east side of the Andes and the Amazonian basin in the Department of San Martín. Both viruses later were recovered from mosquitoes collected above the slope between the west side of the Andes and the coast (Department of Piura) in humid subtropical areas associated with the Piura River basin. In this region, PHSV was isolated from Anopheles albimanus and YUOV was isolated from Ae. scapularis. We discuss the ecology of vector mosquitoes during the outbreaks in the areas where these mosquitoes were found.

Bluetongue and other orbiviruses in South America: gaps and challenges.

South America (SA) has the ideal climatic conditions for occurrence of Bluetongue virus (BTV) and other orbiviruses. Based on serological evidence of BTV circulation, the virus is widespread across SA. However, little knowledge has been acquired about BTV origin and distribution, and circulation of specific serotypes is almost non­existent. The first barrier to a better understanding of Bluetongue (BT) in SA concerns its recognition in the field, as most infections of seropositive ruminants are unapparent in endemic areas. There are few reports on BTV isolation in SA, many of them from viraemic asymptomatic animals. Among the known competent BTV vectors, Culicoides insignis is the most abundant species in SA. However, information about biological characteristics and competence of various other Culicoides species described in SA is missing. The few reports on BT outbreaks lead to an underestimation of the disease impact on the continent economy. To overcome these major gaps, it is necessary to: improve diagnostic structure and disease recognition in the field; identify BTV serotypes and their distribution in different SA areas; and to study the biology and epidemiology of Culicoides. Furthermore, it is important to have a surveillance system for BT, as well as contingency plans for possible outbreaks in SA.

Genetic and biological characterization of selected Changuinola viruses (Reoviridae, Orbivirus) from Brazil.

The genus Orbivirus of the family Reoviridae comprises 22 virus species including the Changuinola virus (CGLV) serogroup. The complete genome sequences of 13 CGLV serotypes isolated between 1961 and 1988 from distinct geographical areas of the Brazilian Amazon region were obtained. All viral sequences were obtained from single-passaged CGLV strains grown in Vero cells. CGLVs are the only orbiviruses known to be transmitted by phlebotomine sandflies. Ultrastructure and molecular analysis by electron microscopy and gel electrophoresis, respectively, revealed viral particles with typical orbivirus size and morphology, as well as the presence of a segmented genome with 10 segments. Full-length nucleotide sequencing of each of the ten RNA segments of the 13 CGLV serotypes provided basic information regarding the genome organization, encoded proteins and genetic traits. Segment 2 (encoding VP2) of the CGLV is uncommonly larger in comparison to those found in other orbiviruses and shows varying sizes even among different CGLV serotypes. Phylogenetic analysis support previous serological findings, which indicate that CGLV constitutes a separate serogroup within the genus Orbivirus. In addition, six out of 13 analysed CGLV serotypes showed reassortment of their genome segments.

Frequência de anticorpos contra o vírus da língua azul em ovinos do estado do Ceará, Brasil / Antibodies against the bluetongue virus in sheep flocks of Ceará state, Brazil

O objetivo deste trabalho foi avaliar a ocorrência de ovinos soropositivos para o vírus da línguaazul (VLA) no Estado do Ceará, Brasil, e analisar as proteínas imunogênicas das cepas virais circulantes nesses rebanhos. O teste de imunodifusão em gel de agarose (IDGA) foi utilizado para pesquisar 271 amostras de soro oriundas de 16 rebanhos. Os resultados demonstraram que 27,3% (74/271) das amostras analisadas apresentaram anticorpos contra o agente e 68,8% (11/16) das propriedades tiveram animais positivos. O immunoblotting (IB) foi utilizado para analisar as proteínas imunogênicas do VLA a partir dos soros de animais positivos no IDGA. Os soros demonstraram forte reação contra a proteína viral VP2. Para o VLA, das sete proteínas estruturais, a VP2 é a principal a estimular a resposta imune protetora. Concluiu-se que a soropositividade para a língua azul (LA) nos rebanhos ovinos estudados no Ceará é alta, apesar dos animais não apresentarem sinais clínicos, indicativo de que o vírus ocorra de forma endêmica. Além disso, a resistência à doença apresentada pelos animais pode estar relacionada com a forte reação imunológica desses à proteína VP2. Sendo assim, outros estudos são necessários para melhor esclarecer a situação epidemiológica da LA no país, através da identificação dos vetores e sorotipos virais circulantes nas diferentes regiões. (AU)

Antibodies against the bluetongue virus in sheep flocks of Ceará state, Brazil. The objective of this work was to verify the occurrence of sheep serologically positive for bluetongue virus (BTV) in the state of Ceará, Brazil, and analyze immunogenic proteins of circulating viral strains in these flocks. The agar gel immunodifusion test (AGID) was used to examine 271 serum samples from 16 herds. The results demonstrated that 27.3% (74/271) ofthe analyzed samples presented antibodies for the agent, and that 68.8% (11/16) of the propertiespresented positive animals. Immunoblotting (IB) was used to analyze the immunogenicproteins of BTV derived from AGID positive sera. Sera showed strong reaction against viral protein VP2. Of the seven BTV structural proteins, VP2 is the major protein to elicit protective immuneresponses. It was concluded that bluetongue (BT) seropositivity in sheep flocks studied in Ceará is high, despite that the animal's do not show clinical signs, indicating that it occurs in an endemic form. The animals resistance to the disease may be related to the strong immune response to the protein VP2. Therefore, further studies are needed to better clarify the epidemiological situation of BT in Brazilian sheep flocks, through the identification of viral vectors and serotypes circulating in different regions. (AU)

Frequência de anticorpos contra o vírus da língua azul em ovinos do estado do Ceará, Brasil / Antibodies against the bluetongue virus in sheep flocks of Ceará state, Brazil

O objetivo deste trabalho foi avaliar a ocorrência de ovinos soropositivos para o vírus da línguaazul (VLA) no Estado do Ceará, Brasil, e analisar as proteínas imunogênicas das cepas virais circulantes nesses rebanhos. O teste de imunodifusão em gel de agarose (IDGA) foi utilizado para pesquisar 271 amostras de soro oriundas de 16 rebanhos. Os resultados demonstraram que 27,3% (74/271) das amostras analisadas apresentaram anticorpos contra o agente e 68,8% (11/16) das propriedades tiveram animais positivos. O immunoblotting (IB) foi utilizado para analisar as proteínas imunogênicas do VLA a partir dos soros de animais positivos no IDGA. Os soros demonstraram forte reação contra a proteína viral VP2. Para o VLA, das sete proteínas estruturais, a VP2 é a principal a estimular a resposta imune protetora. Concluiu-se que a soropositividade para a língua azul (LA) nos rebanhos ovinos estudados no Ceará é alta, apesar dos animais não apresentarem sinais clínicos, indicativo de que o vírus ocorra de forma endêmica. Além disso, a resistência à doença apresentada pelos animais pode estar relacionada com a forte reação imunológica desses à proteína VP2. Sendo assim, outros estudos são necessários para melhor esclarecer a situação epidemiológica da LA no país, através da identificação dos vetores e sorotipos virais circulantes nas diferentes regiões.

Antibodies against the bluetongue virus in sheep flocks of Ceará state, Brazil. The objective of this work was to verify the occurrence of sheep serologically positive for bluetongue virus (BTV) in the state of Ceará, Brazil, and analyze immunogenic proteins of circulating viral strains in these flocks. The agar gel immunodifusion test (AGID) was used to examine 271 serum samples from 16 herds. The results demonstrated that 27.3% (74/271) ofthe analyzed samples presented antibodies for the agent, and that 68.8% (11/16) of the propertiespresented positive animals. Immunoblotting (IB) was used to analyze the immunogenicproteins of BTV derived from AGID positive sera. Sera showed strong reaction against viral protein VP2. Of the seven BTV structural proteins, VP2 is the major protein to elicit protective immuneresponses. It was concluded that bluetongue (BT) seropositivity in sheep flocks studied in Ceará is high, despite that the animal's do not show clinical signs, indicating that it occurs in an endemic form. The animals’ resistance to the disease may be related to the strong immune response to the protein VP2. Therefore, further studies are needed to better clarify the epidemiological situation of BT in Brazilian sheep flocks, through the identification of viral vectors and serotypes circulating in different regions.

Anticorpos contra o vírus da língua azul em rebanhos ovinos da microrregião de Juazeiro, Bahia / Antibodies against the bluetongue virus in sheep flocks of Bahia state, Brazil

O objetivo desta pesquisa foi verificar a frequência de ovinos soropositivos para o vírus da língua azul na microrregião de Juazeiro, Bahia. O teste de imunodifusão em gel de ágar (IDGA) foi utilizado para pesquisar 469 amostras de soro oriundas de 58 rebanhos. Durante as colheitas, um questionário foi aplicado a cada criador a fim de se obter dados sobre o sistema de criação e correlacioná-los com a sorologia. Os resultados demonstraram que 0,43% (2/469) das amostras analisadas apresentaram anticorpos contra o agente. Esta região é caracterizada pelo clima semiárido e pela predominância do tipo de exploração extensiva, com presença de animais nativos, mestiços e sem raça definida para produção de carne e pele, com baixa produtividade e tecnificação.

The objective of this work was to verify the frequency of sheep with positive serology for Bluetongue virus in the micro-region of Juazeiro, Bahia State, Brazil. The agar gel immunodifusion test (AGID) was used to examine 469 serum samples of 58 herds. During collection, an epidemiological questionnaire was applied to each farmer. The results demonstrated that 0.43% (2/469) of the analyzed samples presented antibodies for the agent. This region is characterized by a semi-arid climate, and the predominant livestock management system is the extensive one, with a presence of native and crossbred animals, aiming at the production of meat and fleece, with low productivity and technification.

Peruvian horse sickness virus and Yunnan orbivirus, isolated from vertebrates and mosquitoes in Peru and Australia.

During 1997, two new viruses were isolated from outbreaks of disease that occurred in horses, donkeys, cattle and sheep in Peru. Genome characterization showed that the virus isolated from horses (with neurological disorders, 78% fatality) belongs to a new species the Peruvian horse sickness virus (PHSV), within the genus Orbivirus, family Reoviridae. This represents the first isolation of PHSV, which was subsequently also isolated during 1999, from diseased horses in the Northern Territory of Australia (Elsey virus, ELSV). Serological and molecular studies showed that PHSV and ELSV are very similar in the serotype-determining protein (99%, same serotype). The second virus (Rioja virus, RIOV) was associated with neurological signs in donkeys, cattle, sheep and dogs and was shown to be a member of the species Yunnan orbivirus (YUOV). RIOV and YUOV are also almost identical (97% amino acid identity) in the serotype-determining protein. YUOV was originally isolated from mosquitoes in China.