Congenital abnormalities and arthrogryposis in newly born lambs in Al Muthanna province Iraq. Suspicion of Akabane virus infection / Anormalidades congênitas e artrogripose em cordeiros recém-nascidos na província de Al Muthanna, Iraque. Suspeita de infecção pelo vírus Akabane

Akabane virus, a member of the Orthobunyavirus genus in the family Bunyaviridae, causes congenital abnormalities and arthrogryposis with hydrocephalus or hydroencephaly in ruminants. This study intends to describe the clinical signs, gross and histopathological features seen in 25 affected lambs in an outbreak of congenital arthrogryposis with hydrocephalus or hydranencephaly in Al-Muthanna governorate, Iraq after a large number of stillbirths and musculoskeletal deformities from October 2017 to May 2018. Skeletal muscle hypoplasia was seen in the limbs of the affected lambs accompanied with severe arthrogryposis and gross visible brain malformations. In addition, fetal mummifications, stillbirths, and dead lambs were also seen. The most histopathological features in muscle fibers were degenerative lesions and absences of cross-striation accompanied with mild infiltration of neutrophils and mononuclear cells in severely affected lambs. The meninges of affected lambs revealed fused membranes with focal areas of fibrous thickenings and necrotic debris. In conclusion, according to clinical signs, gross and histopathological investigations, Akabane virus, a member of the Orthobunyavirus genus in the family Bunyaviridae, causes congenital abnormalities and arthrogryposis with hydrocephalus or hydroencephaly in ruminants and could be the cause of this outbreak, although future studies must be performed to confirm the etiology of this outbreak. Moreover, other causes of hydrocephalus or cerebellar malformation, such as Schmallenberg virus, bluetongue virus and border disease virus and teratogenic plants that lead to arthrogryposis, have to be investigated. Also, the authorities should take prevention and control measurements to stop the replication of arthropod vectors.(AU)

O presente trabalho descreve os sinais clínicos, as lesões macroscópicas e os aspectos histológicos observados em 25 cordeiros acometidos em um surto de artrogripose congênita com hidrocéfalo ou hidrocefalia registrado no Iraque, governadoria Al-Muthama após a ocorrência de nascimentos prematuros e deformidades músculo-esqueléticas no período compreendido entre outubro de 2017 e maio de 2018. A hipoplasia músculo-esquelética foi observada nos membros dos cordeiros afetados, acompanhada de severa artrogripose e malformações cerebrais, grosseiras visíveis, além de mumificações fetais, nascimentos prematuros e morte de cordeiros. Os principais aspectos histopatológicos nas fibras musculares foram lesões degenerativas e ausências da estriação cruzada acompanhada de leve infiltração de neutrófilos e células mononucleares dos cordeiros severamente afetados. As meninges dos cordeiros afetados apresentaram fusão de membranas com áreas focais de espessamento fibroso e debris necróticos. O vírus Akabane, um membro do gênero Orthobunyavirus, da família Bunyaviridae, causa anormalidades congênitas e artrogripose com hidrocéfalo e hidrocefalia em ruminantes e poderá vir a ser a causa do presente surto. Os autores recomendam a realização de novos estudos com investigações epidemiológicas e isolamento do agente causal. Contudo, outras causas de hidrocéfalo ou malformações cerebrais como as determinadas pelo vírus Schmallenberg, vírus da língua azul e vírus da doença de border, bem como de plantas teratogênicas que determinam a artrogripose, também deverão ser investigadas. As autoridades sanitárias deverão tomar medidas de prevenção e controle para bloquear a replicação do vírus em artrópodes vetores.(AU)

Analysis of Five Arboviruses and Culicoides Distribution on Cattle Farms in Jeollabuk-do, Korea

Arthropod-borne viruses (Arboviruses) are transmitted by arthropods such as Culicoides biting midges and cause abortion, stillbirth, and congenital malformation in ruminants, apparently leading to economic losses to farmers. To monitor the distribution of Culicoides and to determine their relationship with different environmental conditions (temperature, humidity, wind speed, and altitude of the farms) on 5 cattle farms, Culicoides were collected during summer season (May-September) in 2016 and 2017, and analyzed for identification of species and detection of arboviruses. About 35% of the Culicoides were collected in July and the collection rate increased with increase in temperature and humidity. The higher altitude where the farms were located, the more Culicoides were collected on inside than outside. In antigen test of Culicoides against 5 arboviruses, only Chuzan virus (CHUV) (2.63%) was detected in 2016. The Akabane virus (AKAV), CHUV, Ibaraki virus and Bovine ephemeral fever virus (BEFV) had a positive rate of less than 1.8% in 2017. In antigen test of bovine whole blood, AKAV (12.96%) and BEFV (0.96%) were positive in only one of the farms. As a result of serum neutralization test, antibodies against AKAV were generally measured in all the farms. These results suggest that vaccination before the season in which the Culicoides are active is probably best to prevent arbovirus infections.

Mosquitoes, midges and related arboviruses in southeast Sichuan province / 中华流行病学杂志

Objective: To investigate the distribution patterns of mosquitoes, midges and related arboviruses in Sichuan province. Methods: Blood-sucking insects were collected from houses and pens, using the ultraviolet lights. Mosquito samples were classified according to morphologic characteristics and then stored at liquid nitrogen. All samples were incubated with BHK-21 and C6/36 cells for virus isolation and then detected for their viral genes. Sequences of the virus were identified and analyzed by molecular biological software, such as BioEdit 7.0.5.3, MEGA 6.0. Results: In total, 17 019 mosquitoes from 3 genera and 4 species and 12 700 midges were collected from the southeast regions of Sichuan province in 2016 and 2017. Among them, 79.4% (13 519/17 019) belonged to Culex tritaeniorhynchus with 11.1% (1 897/17 019) as Armigeres subalbatus, 5.5% (930/17 019) were Anopheles sinensis and 4.0% (673/17 019) were Anopheles sinensis 3 virus strains that isolated from Culex tritaeniorhynchus were identified as typeⅠ Japanese encephalitis virus. Seven pools of mosquitoes isolated from Hejiang county were identified Japanese encephalitis virus gene positive through PCR amplification. With 4 pool midges were detected positive for Akabane virus through PCR gene amplification while midges samples didn't have virus isolates. Conclusions: Culex tritaeniorhynchus appeared the predominant species in the southeast regions of Sichuan. Japanese encephalitis virus transmitted by mosquitoes and Akabane virus by midges were prevalent in southeast Sichuan province.

Mosquitoes, midges and related arboviruses in southeast Sichuan province / 中华流行病学杂志

Objective To investigate the distribution patterns of mosquitoes,midges and related arboviruses in Sichuan province.Methods Blood-sucking insects were collected from houses and pens,using the ultraviolet lights.Mosquito samples were classified according to morphologic characteristics and then stored at liquid nitrogen.All samples were incubated with BHK-21 and C6/36 cells for virus isolation and then detected for their viral genes.Sequences of the virus were identified and analyzed by molecular biological software,such as BioEdit 7.0.5.3,MEGA 6.0.Results In total,17 019 mosquitoes from 3 genera and 4 species and 12 700 midges were collected from the southeast regions of Sichuan province in 2016 and 2017.Among them,79.4％ (13 519/17 019) belonged to Culex tritaeniorhynchus with 11.1％ (1 897/17 019) as Armigeres subalbatus,5.5％ (930/17 019) were Anopheles sinensis and 4.0％ (673/17 019) were Anopheles sinensis 3 virus strains that isolated from Culex tritaeniorhynchus were identified as type Ⅰ Japanese encephalitis virus.Seven pools of mosquitoes isolated from Hejiang county were identified Japanese encephalitis virus gene positive through PCR amplification.With 4 pool midges were detected positive for Akabane virus through PCR gene amplification while midges samples didn't have virus isolates.Conclusions Culex tritaeniorhynchus appeared the predominant species in the southeast regions of Sichuan.Japanese encephalitis virus transmitted by mosquitoes and Akabane virus by midges were prevalent in southeast Sichuan province.

Development of inactivated Akabane and bovine ephemeral fever vaccine for cattle / 대한수의학회지

Akabane and bovine ephemeral fever (BEF) viruses cause vector-borne diseases. In this study, inactivated Akabane virus (AKAV)+Bovine ephemeral fever virus (BEFV) vaccines with or without recombinant vibrio flagellin (revibFlaB) protein were expressed in a baculovirus expression system to measure their safety and immunogenicity. Blood was collected from mice, guinea pigs, sows, and cattle that had been inoculated with the vaccine twice. Inactivated AKAV+BEFV vaccine induced high virus neutralizing antibody (VNA) titer against AKAV and BEFV in mice and guinea pigs. VNA titers against AKAV were higher in mice and guinea pigs immunized with the inactivated AKAV+ BEFV vaccine than in animals inoculated with vaccine containing revibFlaB protein. Inactivated AKAV+BEFV vaccine elicited slightly higher VNA titers against AKAV and BEFV than the live AKAV and live BEFV vaccines in mice and guinea pigs. In addition, the inactivated AKAV+BEFV vaccine was safe, and induced high VNA titers, ranging from 1 : 64 to 1 : 512, against both AKAV and BEFV in sows and cattle. Moreover, there were no side effects observed in any treated animals. These results indicate that the inactivated AKAV+BEFV vaccine could be used in cattle with high immunogenicity and good safety.

Apoptosis in Vero cells infected with Akabane, Aino and Chuzan virus

Akabane, Aino and Chuzan virus are arthropod-borne (arbo)viruses mainly associated with reproductive failures in cattle. We investigated apoptosis in Vero cells (C-1586) infected with Akabane, Aino and Chuzan virus. The fragmentation of chromosomal DNA was simultaneously detected with the progress of cytopathic effect from 48 hr to 72 hr post infection, depending on viruses. Although the treatment of cycloheximide blocked apoptosis in Vero cells infected with three viruses, actinomycin D did not prevent DNA oligomerization, thus indicating that de novo viral protein synthesis is critical for viral apoptosis. In addition, the activation of caspase-3 was also detected in Vero cells by indirect fluorescent assay. From the present results, it is of future interest whether apoptotic characteristics of these viruses are related to pathogenecity in vivo.