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Metwally S, Bkear N, Samir M, Hamada R, Elshafey B, Batiha G, Almanaa TN, Sobhy K, Badr Y. The First Serological Detection and Risk Factors Analysis of Akabane Virus in Egyptian Cattle. Animals (Basel) 2023; 13:1849. [PMID: 37889776 PMCID: PMC10252070 DOI: 10.3390/ani13111849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 05/26/2023] [Accepted: 05/31/2023] [Indexed: 10/29/2023] Open
Abstract
Akabane virus (AKAV) is an insect-borne virus belonging to the genus Orthobunyavirus of the family Peribunyaviridae. It is the etiologic agent of Akabane disease (AD), which emerged in Asia, Australia, and the Middle East causing severe economic losses among domestic and wild animals. AKAV has not received enough attention in Egypt, and its evidence among Egyptian animals has never been reported. Therefore, this study used ELISA assay to investigate the seroprevalence of AKAV among Egyptian dairy and beef cattle in eight localities of Beheira province, north Egypt. Out of 368 investigated plasma samples, the overall AKAV seroprevalence was 54.3% (95% CI: 50.8-61.4). AKAV antibodies were detected in all examined cattle farms (7/7) and the majority of abattoirs (8/9). Age, sex, breed, and location of the tested cattle were analyzed as risk factors for AKAV infection. A higher significant increase in seropositivity was obtained in cattle who were aged >5 years (p < 0.0001; OR = 9.4), females (p < 0.0001, OR = 8.3), or Holstein breed (p < 0.0001, OR = 22.6) than in younger ages, males, and Mixed and Colombian zebu breeds, respectively. Moreover, a significant variation in AKAV seroprevalence between the tested locations was noticed. Ultimately, a multivariable analysis concluded that age (p = 0.002, OR = 3.32, 95% CI = 1.57-7.04) and breed (p = 0.03, OR = 1.69, 95% CI = 1.05-2.72) were significant risks for AKAV infection. In conclusion, this study is the first to detect AKAV infection in Egyptian animals.
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Affiliation(s)
- Samy Metwally
- Division of Infectious Diseases, Department of Animal Medicine, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
- Laboratory of Global Infectious Diseases Control Science, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-Ku, Tokyo 113-8657, Japan
| | - Nabil Bkear
- Division of Infectious Diseases, Department of Animal Medicine, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
| | - Marwa Samir
- Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
| | - Rania Hamada
- Division of Clinical Pathology, Department of Pathology, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
| | - Besheer Elshafey
- Division of Internal Medicine, Department of Animal Medicine, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
| | - Gaber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
| | - Taghreed N. Almanaa
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia;
| | - Kamel Sobhy
- Department of Theriogenology, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
| | - Yassien Badr
- Division of Infectious Diseases, Department of Animal Medicine, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt;
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Yanase T, Murota K, Hayama Y. Endemic and Emerging Arboviruses in Domestic Ruminants in East Asia. Front Vet Sci 2020; 7:168. [PMID: 32318588 PMCID: PMC7154088 DOI: 10.3389/fvets.2020.00168] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 03/10/2020] [Indexed: 02/04/2023] Open
Abstract
Epizootic congenital abnormalities caused by Akabane, Aino, and Chuzan viruses have damaged the reproduction of domestic ruminants in East Asia for many years. In the past, large outbreaks of febrile illness related to bovine ephemeral fever and Ibaraki viruses severely affected the cattle industry in that region. In recent years, vaccines against these viruses have reduced the occurrence of diseases, although the viruses are still circulating and have occasionally caused sporadic and small-scaled epidemics. Over a long-term monitoring period, many arboviruses other than the above-mentioned viruses have been isolated from cattle and Culicoides biting midges in Japan. Several novel arboviruses that may infect ruminants (e.g., mosquito- and tick-borne arboviruses) were recently reported in mainland China based on extensive surveillance. It is noteworthy that some are suspected of being associated with cattle diseases. Malformed calves exposed to an intrauterine infection with orthobunyaviruses (e.g., Peaton and Shamonda viruses) have been observed. Epizootic hemorrhagic disease virus serotype 6 caused a sudden outbreak of hemorrhagic disease in cattle in Japan. Unfortunately, the pathogenicity of many other viruses in ruminants has been uncertain, although these viruses potentially affect livestock production. As global transportation grows, the risk of an accidental incursion of arboviruses is likely to increase in previously non-endemic areas. Global warming will also certainly affect the distribution and active period of vectors, and thus the range of virus spreads will expand to higher-latitude regions. To prevent anticipated damages to the livestock industry, the monitoring system for arboviral circulation and incursion should be strengthened; moreover, the sharing of information and preventive strategies will be essential in East Asia.
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Affiliation(s)
- Tohru Yanase
- Kyushu Research Station, National Institute of Animal Health, NARO, Kagoshima, Japan
| | - Katsunori Murota
- Kyushu Research Station, National Institute of Animal Health, NARO, Kagoshima, Japan
| | - Yoko Hayama
- Viral Disease and Epidemiology Research Division, National Institute of Animal Health, NARO, Tsukuba, Japan
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Tang HB, Ren P, Qin S, Lin J, Bai A, Qin S, Chen F, Liu J, Wu J. Isolation, genetic analysis of the first Akabane virus from goat in China. J Vet Med Sci 2019; 81:1445-1449. [PMID: 31378772 PMCID: PMC6863719 DOI: 10.1292/jvms.18-0602] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Akabane virus (AKAV) is an important insect-borne virus belonging to the genus
Orthobunyavirus, the Peribunyaviridae family. An AKAV
defined as GXDH 01 here, was isolated for the first time from blood from a sentinel goat
in China in 2016, and its full-length open reading frames (ORFs) were sequenced in this
study. Sequence analysis suggested that the isolate GXDH 01 probably had undergone a
reassortment incident and acquired L segments from other strain originating from an
attenuated vaccine, such as OBE-1. This study aims to provide more understanding as to the
origin and epidemiology of AKAV in China.
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Affiliation(s)
- Hai-Bo Tang
- Guangxi Veterinary Research Institute, Nanning 530001, China.,College of Basic Medicine, Guangxi University of Chinese Medicine, Nanning 530001, China.,Guangxi Key Laboratory of Translational Medicine for Treating High-Incidence Infectious Diseases with Integrative Medicine, Nanning, 530200, China
| | - Pengfei Ren
- Guangxi Veterinary Research Institute, Nanning 530001, China
| | - Shuying Qin
- Guangxi Veterinary Research Institute, Nanning 530001, China
| | - Jun Lin
- Guangxi Veterinary Research Institute, Nanning 530001, China
| | - Anbin Bai
- Guangxi Veterinary Research Institute, Nanning 530001, China
| | - Shaomin Qin
- Guangxi Veterinary Research Institute, Nanning 530001, China
| | - Fenglian Chen
- Guangxi Veterinary Research Institute, Nanning 530001, China
| | - Jinfeng Liu
- Guangxi Veterinary Research Institute, Nanning 530001, China
| | - Jianmin Wu
- Guangxi Veterinary Research Institute, Nanning 530001, China
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Kirkland PD. Arbovirus infections of animals: congenital deformities, encephalitis, sudden death and blindness. MICROBIOLOGY AUSTRALIA 2018. [DOI: 10.1071/ma18030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Viruses from five different taxonomic families have been shown to be the cause of disease outbreaks in either domesticated or wild animals. These include viruses spread by both mosquitoes and biting midges from the genus Culicoides, especially C. brevitarsis. A number of arboviruses also present significant impediments to the international movement of live animals, semen and embryos.
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Post-epidemic Schmallenberg virus circulation: parallel bovine serological and Culicoides virological surveillance studies in Ireland. BMC Vet Res 2016; 12:234. [PMID: 27756302 PMCID: PMC5069804 DOI: 10.1186/s12917-016-0865-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 10/07/2016] [Indexed: 11/29/2022] Open
Abstract
Background Schmallenberg virus (SBV) emerged in northern-Europe in 2011 resulting in an epidemic of ruminant abortions and congenital malformations throughout the continent. In the years following the epidemic there have been reports of SBV overwintering and continued circulation in several European countries. When the population-level of immunity declines in exposed regions, re-introduction of SBV could result in further outbreaks of Schmallenberg disease. The aims of this study were to determine the SBV seroprevalence in previously exposed Irish dairy herds in 2014 and to investigate if SBV continued to circulate in these herds in the three years (2013–2015) following the Irish Schmallenberg epidemic. Whole-herd SBV serosurveillance was conducted in 26 herds before (spring) and following the 2014 vector-season (winter), and following the 2015 vector-season (winter). In spring 2014, 5,531 blood samples were collected from 4,070 cows and 1,461 heifers. In winter 2014, 2,483 blood samples were collected from 1,550 youngstock (8–10 months old) and a subsample (n = 933; 288 cows, 645 heifers) of the seronegative animals identified in the spring. Youngstock were resampled in winter 2015. Culicoides spp. were collected in 10 herds during the 2014 vector-season and analysed for SBV; a total of 138 pools (3,048 Culicoides) from 6 SBV vector species were tested for SBV RNA using real-time PCR. Results In spring 2014, animal-level seroprevalence was 62.5 % (cows = 84.7 %; heifers = 0.6 %). Within-herd seroprevalence ranged widely from 8.5 %–84.1 % in the 26 herds. In winter 2014, 22 animals (0.9 %; 10 cows, 5 heifers, 7 youngstock) originating in 17 herds (range 1–4 animals/herd) tested seropositive. In winter 2015 all youngstock, including the 7 seropositive animals in winter 2014, tested seronegative suggesting their initial positive result was due to persistence of maternal antibodies. All of the Culicoides pools examined tested negative for SBV-RNA. Conclusions SBV appears to have recirculated at a very low level in these herds during 2013 and 2014, while there was no evidence of SBV infection in naïve youngstock during 2015. A large population of naïve animals was identified and may be at risk of infection in future years should SBV re-emerge and recirculate as it has done in continental Europe.
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Lee H, Jeong H, Park S, Yang MS, Kim J, Bae J, Kwon Y, Kim MS, Oem JK, Lee MH, Lim CW, Kim B. Experimental infection of cows with newly isolated Akabane virus strain (AKAV-7) causing encephalomyelitis. Vet Res 2016; 47:62. [PMID: 27287214 PMCID: PMC4901474 DOI: 10.1186/s13567-016-0349-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 05/25/2016] [Indexed: 11/25/2022] Open
Abstract
Akabane virus (AKAV), an arthropod-transmitted bunyavirus, is a major cause of congenital abnormalities and encephalomyelitis in ruminants. In 2010, there was a major outbreak of encephalomyelitis in Korea and fifteen AKAV strains, including AKAV-7, were isolated from cows. To identify the neuropathogenicity of AKAV-7, we performed experimental infection of cows. Six-month-old female Korean Holstein dairy cattle were inoculated with AKAV-7 by various routes, including intracerebral (IC), intrasubarachnoid space (IS), subcutaneous (SC) and intravenous (IV); a separate group was vaccinated before intravenous infection. Five of the six cows in the IC group and two of the six cows in the IS group showed clinical signs such as locomotor ataxia and paralysis of the hind limbs. Three of six cows died after IC infection 9–12 days post infection (dpi). Histopathologic changes such as nonsuppurative encephalomyelitis were confirmed in various parts of the central nervous system in the IC, IS and SC groups. Early onset of neutralizing antibodies in the serum and lower viral mRNA levels in the peripheral blood mononuclear cells (PBMCs) and various tissues in the vaccinated group was noticeable compared to the unvaccinated group (IV group). We suggest that the AKAV vaccine currently used in Korea may be partially effective for protection against AKAV-7 in cows.
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Affiliation(s)
- Hyeyeoun Lee
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Hansol Jeong
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Surim Park
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Myeon-Sik Yang
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Jongwon Kim
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Jaehyun Bae
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Yonghwan Kwon
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Min-Su Kim
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Jae-Ku Oem
- National Institute of Environmental Research, Ministry of environment, Incheon, 22689, Korea
| | - Myoung-Heon Lee
- Division of Animal Diseases Diagnosis, Animal and Plant Quarantine Agency, Gimcheon, 39660, Korea
| | - Chae-Woong Lim
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea
| | - Bumseok Kim
- College of Veterinary Medicine, Chonbuk National University, Iksan, 54596, Korea.
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Spatial epidemiological analysis of bovine encephalomyelitis outbreaks caused by Akabane virus infection in western Japan in 2011. Trop Anim Health Prod 2016; 48:843-7. [PMID: 26898692 DOI: 10.1007/s11250-016-1014-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/09/2016] [Indexed: 10/22/2022]
Abstract
Akabane disease, which is distributed in temperate and tropical regions in the world, is a vector-borne disease of ruminants caused by the Akabane virus, transmitted by Culicoides biting midges. In 2011, outbreaks of Akabane viral encephalomyelitis occurred in the Shimane Prefecture in western Japan. In this study, a spatial epidemiological analysis was conducted to understand environmental factors associated with the spread of Akabane disease. By applying a conditional autoregressive model, the relationship between infection and environmental variables was explored. The results showed that the dominance of farmlands and the presence of infected farms within a 3-km radius had a significant effect on infection. This result implies that land use, which would relate with the vector habitat, and the presence of neighboring infected farms as a source of infection may have influenced the spread of the disease in this region. These findings provide basic insights into the spread of Akabane disease and useful suggestions for developing a surveillance program and preventive measures against the disease.
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Lee JH, Seo HJ, Park JY, Kim SH, Cho YS, Kim YJ, Cho IS, Jeoung HY. Detection and differentiation of Schmallenberg, Akabane and Aino viruses by one-step multiplex reverse-transcriptase quantitative PCR assay. BMC Vet Res 2015; 11:270. [PMID: 26497392 PMCID: PMC4619357 DOI: 10.1186/s12917-015-0582-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 10/14/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Schmallenberg virus (SBV), Akabane virus (AKAV) and Aino virus (AINV) are members of the Simbu serogroup within the genus Orthobunyavirus, family Bunyaviridae, which can cause reproductive disorders including abortion, stillbirth and congenital malformation in ruminants. Because, the clinical signs are similar, confirmatory diagnosis requires viral detection to differentiate infection between these three viruses. METHODS In this study, a one-step multiplex reverse-transcriptase quantitative PCR (one-step mRT-qPCR) was developed for the simultaneous detection and differentiation of SBV, AKAV and AINV. RESULTS The detection limit of the one-step mRT-qPCR for SBV, AKAV and AINV were 2.4 copies (10 (0.6) TCID 50/ml), 96.2 copies (10 (1.5) TCID 50/ml) and 52.3 copies (10 (1.2) TCID 50/ml), respectively. Various field samples such as bovine serum, bovine whole blood, bovine brain, goat serum and Culicoides were analyzed using the one-step mRT-qPCR and compared with previously published RT-qPCRs. The test results of the field samples were identical for the one-step mRT-qPCR and RT-qPCRs, which showed all samples to be negative for SBV, AKAV and AINV, except for one bovine brain sample (1/123) that was positive for AKAV. CONCLUSION The one-step mRT-qPCR allows for the simultaneous detection of three viral pathogens (SBV, AKAV and AINV) that cause reproductive failure.
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Affiliation(s)
- Ji-Hye Lee
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
| | - Hyun-Ji Seo
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
| | - Jee-Yong Park
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
| | - Sung-Hee Kim
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
| | - Yun Sang Cho
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
| | - Yong-Joo Kim
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
| | - In-Soo Cho
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
| | - Hye-Young Jeoung
- Animal and Plant Quarantine Agency, Anyang, Gyeonggi-do, 430-824, Republic of Korea.
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Agerholm JS, Hewicker-Trautwein M, Peperkamp K, Windsor PA. Virus-induced congenital malformations in cattle. Acta Vet Scand 2015; 57:54. [PMID: 26399846 PMCID: PMC4581091 DOI: 10.1186/s13028-015-0145-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 08/30/2015] [Indexed: 11/18/2022] Open
Abstract
Diagnosing the cause of bovine congenital malformations (BCMs) is challenging for bovine veterinary practitioners and laboratory diagnosticians as many known as well as a large number of not-yet reported syndromes exist. Foetal infection with certain viruses, including bovine virus diarrhea virus (BVDV), Schmallenberg virus (SBV), blue tongue virus (BTV), Akabane virus (AKAV), or Aino virus (AV), is associated with a range of congenital malformations. It is tempting for veterinary practitioners to diagnose such infections based only on the morphology of the defective offspring. However, diagnosing a virus as a cause of BCMs usually requires laboratory examination and even in such cases, interpretation of findings may be challenging due to lack of experience regarding genetic defects causing similar lesions, even in cases where virus or congenital antibodies are present. Intrauterine infection of the foetus during the susceptible periods of development, i.e. around gestation days 60-180, by BVDV, SBV, BTV, AKAV and AV may cause malformations in the central nervous system, especially in the brain. Brain lesions typically consist of hydranencephaly, porencephaly, hydrocephalus and cerebellar hypoplasia, which in case of SBV, AKAV and AV infections may be associated by malformation of the axial and appendicular skeleton, e.g. arthrogryposis multiplex congenita. Doming of the calvarium is present in some, but not all, cases. None of these lesions are pathognomonic so diagnosing a viral cause based on gross lesions is uncertain. Several genetic defects share morphology with virus induced congenital malformations, so expert advice should be sought when BCMs are encountered.
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Affiliation(s)
- Jørgen S Agerholm
- Section for Veterinary Reproduction and Obstetrics, Department of Large Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlaegevej 68, 1870, Frederiksberg C, Denmark.
| | - Marion Hewicker-Trautwein
- Department of Pathology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559, Hannover, Germany.
| | - Klaas Peperkamp
- Department of Pathology, GD Animal Health, Arnsbergstraat 7, P.O. Box 9, 7400 AA, Deventer, The Netherlands.
| | - Peter A Windsor
- Faculty of Veterinary Science, University of Sydney, Camden, NSW, 2570, Australia.
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Histopathological Studies on the Neuropathogenicity of the Iriki and OBE-1 Strains of Akabane Virus in BALB/cAJcl Mice. J Comp Pathol 2015; 153:140-9. [PMID: 26184805 DOI: 10.1016/j.jcpa.2015.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 06/08/2015] [Accepted: 06/15/2015] [Indexed: 11/23/2022]
Abstract
The OBE-1 strain of Akabane virus infects the fetus via the dam, resulting in abortion or congenital abnormalities in ruminants. In contrast, the Iriki strain of Akabane virus is highly virulent and causes encephalomyelitis by post-natal infection. To clarify the difference in pathogenicity between the two strains, BALB/cAJcl mice were inoculated either intraperitoneally or intracerebrally (IC) with either strain from 3 days to 8 weeks of age. Pathological examination revealed non-suppurative encephalitis in mice inoculated by either route with the Iriki strain. Virus antigens were distributed widely throughout the brain when the virus was inoculated into newborn mice, but distribution was limited to the brainstem in mice inoculated when 8 weeks old. However, brain lesions were observed only in mice inoculated with OBE-1 by the IC route when the mice were 3 days old, but these lesions were mild. To examine the manner of viral spreading, the Iriki strain was inoculated IC or intrastriatally into 8-week-old mice. Viral antigens were distributed prominently throughout the spinal cord as well as the brainstem and various cerebral nuclei, and were present with less prominence in the connective fibres. Virus antigens were also distributed in the subventricular zone, where neuronal stem cells exist. These results show that the neuroinvasiveness of the Iriki strain diminishes with age, while neurovirulence is maintained; however, for the OBE-1 strain both neuroinvasiveness and neurovirulence diminish with age. Furthermore, Akabane virus infects neuronal cells in the brainstem and spreads to the spinal cord via an unidentified transneuronal pathway.
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Kim YH, Oem JK, Lee EY, Lee KK, Kim SH, Lee MH, Park SC. Seroprevalence of five arboviruses in sentinel cattle as part of nationwide surveillance in South Korea, 2009-2012. J Vet Med Sci 2014; 77:247-50. [PMID: 25342637 PMCID: PMC4363032 DOI: 10.1292/jvms.14-0163] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
To investigate the possible circulation of arboviruses in South Korea, nationwide surveillance of five arbovirues was conducted in sentinel calves during 2009−2012. We used serum neutralization tests to investigate the presence of antibodies for the Aino virus, Akabane virus, bovine ephemeral fever virus, Chuzan virus and Ibaraki virus. In 2009, 2011 and 2012, the seropositive rates for these five arboviruses were all less than 14.1%. In 2010, however, the seropositive rates for Aino virus and Akabane virus were 33.2% and 40.2%, respectively. High seropositive rates were also associated with a large-scale outbreak of Akabane viral encephalomyelitis in cattle in southern Korea in 2010. Continued seroprevalence surveillance will be useful for monitoring natural arboviral diseases.
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Affiliation(s)
- Yeon-Hee Kim
- Animal Disease Diagnostic Division, Animal and Plant Quarantine Agency, MAFRA, Anyang 430-757, Republic of Korea
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A serological survey of akabane virus infection in cattle in Sudan. ISRN VETERINARY SCIENCE 2014; 2014:123904. [PMID: 24977042 PMCID: PMC4060564 DOI: 10.1155/2014/123904] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 12/18/2013] [Indexed: 11/22/2022]
Abstract
A cross-sectional survey was carried out in ten states in Sudan to determine seroprevalence and to assess risk factors associated with Akabane virus (AKAV) infection in dairy herds. Serum samples were collected from a total of 361 dairy cattle and tested for antibodies against AKAV using ELISA. The prevalence rates of AKAV antibodies in cattle varied between 69.6% in Khartoum state and 3.3% in Sennar State with an overall prevalence rate of 29.4%. The prevalence rates of AKAV antibodies were significantly associated with breed being high in crossbred (39.9%; P < 0.001); female sex (33%; P < 0.001), and animals in the age group of 2-3 years old (45.3%; P < 0.001). Akabane virus antibodies prevalence was also highly associated with locality (P < 0.001); season being high in winter season (58.1%; P < 0.001); and animals raised under intensive management system (37%; P < 0.001). Among 68 cases suffering from reproductive (abortion and infertility) problems the prevalence rate of AKAV antibodies in animals with infertility problem (76.2%; P < 0.03) was significantly higher than in animals with abortion (48.9%). The study revealed that AKAV infection is highly prevalent in dairy cattle in Sudan and this calls for control strategy to be implemented.
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Oem JK, Kim YH, Kim SH, Lee MH, Lee KK. Serological characteristics of affected cattle during an outbreak of bovine enzootic encephalomyelitis caused by Akabane virus. Trop Anim Health Prod 2013; 46:261-3. [DOI: 10.1007/s11250-013-0468-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2013] [Indexed: 11/30/2022]
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Hulst M, Kortekaas J, Hakze-van der Honing R, Vastenhouw S, Cornellissen J, van Maanen K, Bossers A, Harders F, Stockhofe N, van der Poel W. Genetic characterization of an atypical Schmallenberg virus isolated from the brain of a malformed lamb. Virus Genes 2013; 47:505-14. [PMID: 23996608 DOI: 10.1007/s11262-013-0975-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Accepted: 08/23/2013] [Indexed: 11/28/2022]
Abstract
A novel orthobunyavirus, named "Schmallenberg virus" (SBV), was first detected in the blood of cattle at the end of the summer in Germany in 2011, and subsequently in late autumn from the brain of a stillborn malformed lamb in The Netherlands. Full genome sequences, including 5' and 3' terminal "panhandle" sequences of the L, M, and S segments of the SBV isolated from lamb brain tissue (named HL1) were determined. In addition, a second SBV strain was isolated from the blood of a dairy cow (named F6) also in The Netherlands. This isolate was passaged on Vero cells, and its genome sequence was determined by next-generation sequencing. Alignments of the two genome sequences revealed 4, 12, and 2 amino acid differences in the open reading frames of the L, M, and S segments, respectively. Eleven of a total of 12 amino acid differences were detected in the M segment encoding the ectodomain of the putative structural glycoprotein Gc. Notably, in the HL1 isolate, positions 737-739 are occupied by isoleucine, arginine, and leucine (IRL), whereas in the majority of other sequenced SBV isolates these positions are occupied by threonine, histidine, and proline, respectively. Moreover, in all sheep, goat, and cattle SBV isolates sequenced and published so far, an IRL sequence was never found. This has brought us to the conclusion that the M segment of the HL1 isolate differed markedly from that of other lamb and cow isolates. Whether this atypical variant resulted from adaptation to the ewe, fetus, or insect vector remains to be investigated.
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Affiliation(s)
- Marcel Hulst
- Livestock Research of Wageningen University and Research Centre, P.O. Box 65, 8200 AB, Lelystad, The Netherlands,
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Elbers ARW, Loeffen WLA, Quak S, de Boer-Luijtze E, van der Spek AN, Bouwstra R, Maas R, Spierenburg MAH, de Kluijver EP, van Schaik G, van der Poel WHM. Seroprevalence of Schmallenberg virus antibodies among dairy cattle, the Netherlands, winter 2011-2012. Emerg Infect Dis 2012; 18:1065-71. [PMID: 22709656 PMCID: PMC3376820 DOI: 10.3201/eid1807.120323] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Seroprevalence was highest in the eastern part of the country, bordering Germany, where the virus was first identified. Infections with Schmallenberg virus (SBV) are associated with congenital malformations in ruminants. Because reporting of suspected cases only could underestimate the true rate of infection, we conducted a seroprevalence study in the Netherlands to detect past exposure to SBV among dairy cattle. A total of 1,123 serum samples collected from cattle during November 2011–January 2012 were tested for antibodies against SBV by using a virus neutralization test; seroprevalence was 72.5%. Seroprevalence was significantly higher in the central-eastern part of the Netherlands than in the northern and southern regions (p<0.001). In addition, high (70%–100%) within-herd seroprevalence was observed in 2 SBV-infected dairy herds and 2 SBV-infected sheep herds. No significant differences were found in age-specific prevalence of antibodies against SBV, which is an indication that SBV is newly arrived in the country.
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Affiliation(s)
- Armin R W Elbers
- Department of Epidemiology, Crisis Organisation and Diagnostics, Central Veterinary Institute, part of Wageningen UR, Lelystad, the Netherlands.
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Loeffen W, Quak S, de Boer-Luijtze E, Hulst M, van der Poel W, Bouwstra R, Maas R. Development of a virus neutralisation test to detect antibodies against Schmallenberg virus and serological results in suspect and infected herds. Acta Vet Scand 2012; 54:44. [PMID: 22871162 PMCID: PMC3503834 DOI: 10.1186/1751-0147-54-44] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 07/25/2012] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND At the end of 2011, a new orthobunyavirus, tentatively named Schmallenberg virus (SBV), was discovered in Germany. This virus has since been associated with clinical signs of decreased milk production, watery diarrhoea and fever in dairy cows, and subsequently also with congenital malformations in calves, lambs and goat kids. In affected countries, initial surveillance for the infection was based on examination of malformed progeny. These suspicions were followed up by real-time reverse transcription polymerase chain reaction (RT-PCR) on brain tissue. For epidemiological purposes, a serological assay was, however, needed. RESULTS A virus neutralisation test (VNT) was developed and optimized, and subsequently evaluated. This VNT has a specificity of >99% and the sensitivity is likely also very close to 100%. The assay is highly repeatable and reproducible. The final assay was used to test for antibodies in cows, ewes and does from herds known to be infected or suspected to be so. Targets for sampling in these herds were the mothers of malformed offspring. In herds with an RT-PCR confirmed SBV infection, more than 94% (190 out of 201) of the ewes and 99% (145 out of 146) of the cows were seropositive. In herds with suspicion of SBV infection based on birth of malformed offspring only (no or negative RT-PCR), more than 90% (231 out of 255) of the ewes and 95% (795 out of 834) of the cows were seropositive. In goats, on the other hand, only a low number of seropositives was found: overall 36.4%, being 16 out of 44 goats tested. CONCLUSIONS Given the characteristics of this VNT, it can be used at a relative high throughput for testing of animals for export, surveillance, screening and research purposes, but can also be used as a confirmation test for commercially available enzyme-linked immunosorbent assays (ELISA's) and for (relative) quantification of antibodies.Suspicions of SBV infections that were confirmed by RT-PCR were almost always confirmed by serology in cows. Due to individual registration and identification of cows and calves, affected offspring could almost always be traced back to the mother. Ewes on the other hand were not always the mothers of affected lambs, but were in many cases herd mates with unaffected lambs. This indicated a high within-herd seroprevalence of antibodies against SBV.
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Oem J, Lee K, Kim H, Bae Y, Chung J, Lee O, Roh I. Bovine Epizootic Encephalomyelitis caused by Akabane Virus Infection in Korea. J Comp Pathol 2012; 147:101-5. [DOI: 10.1016/j.jcpa.2012.01.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Revised: 10/03/2011] [Accepted: 01/17/2012] [Indexed: 11/26/2022]
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Oem JK, Yoon HJ, Kim HR, Roh IS, Lee KH, Lee OS, Bae YC. Genetic and pathogenic characterization of Akabane viruses isolated from cattle with encephalomyelitis in Korea. Vet Microbiol 2012; 158:259-66. [PMID: 22464491 DOI: 10.1016/j.vetmic.2012.02.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 02/02/2012] [Accepted: 02/09/2012] [Indexed: 12/12/2022]
Abstract
A large-scale outbreak of Akabane viral encephalomyelitis in cattle was reported in the southern part of Korea in 2010. Fifteen Akabane virus (AKAV) strains were isolated from the brain and spinal cord samples by using BHK-21 and/or HmLu-1 cells. To examine the genetic relationships and characteristics of the isolates, nucleotide sequences of the S, M, and L segments of the 15 isolates were determined and analyzed. Complete sequence analysis of the 15 AKAV isolates showed 99.9-100% amino acid identities, indicating that the 15 isolates originated from a single strain. The S and M RNA segments of a representative isolate (AKAV-7/SKR/2010) were also compared with the segments of representative reference sequences. This AKAV-7/SKR/2010 strain showed the highest identity with the Iriki and KM-1/Br/06 strains. Neighbor-joining phylogenetic trees of S and M RNA segments were constructed. Four representative AKAV isolates were classified into subgroup Ia, which contains the Iriki and KM-1/Br/06 strains recognized to cause encephalomyelitis in calves and adult cattle in Japan. Moreover, experimental intraperitoneal infection was performed using the AKAV-7/SKR/2010 and AKAV-17/SKR/2010 strains to assess pathogenesis in suckling mice. The 2 isolates, genetically related to the Iriki strain, were neurovirulent and caused neurological signs in suckling mice. In contrast, the 93FMX strain and the K0505 strain, related to the OBE-1 strain, were avirulent in mice. The present results indicate that these isolates most likely had originated from the Iriki strain and are closely related to the Iriki strain both genetically and pathogenically.
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Affiliation(s)
- Jae-Ku Oem
- Animal, Plant and Fisheries Quarantine and Inspection Agency, Ministry for Food, Agriculture, Forestry and Fisheries, Anyang, Republic of Korea
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Kessell A, Finnie J, Windsor P. Neurological diseases of ruminant livestock in Australia. IV: viral infections. Aust Vet J 2011; 89:331-7. [PMID: 21864304 DOI: 10.1111/j.1751-0813.2011.00817.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Most viral infections that affect the central nervous system of ruminants are exotic to Australia. As such, this review focuses on viruses of importance in Australian ruminants, including Akabane virus and the ruminant pestiviruses, bovine viral diarrhoea virus and border disease virus, as well as bluetongue virus. Each virus is discussed in terms of pathogenesis, clinical signs and diagnosis.
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Affiliation(s)
- Ae Kessell
- School of Animal and Veterinary Science, Charles Sturt University, Wagga Wagga, New South Wales, Australia.
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Development of inactivated trivalent vaccine for the teratogenic Aino, Akabane and Chuzan viruses. Biologicals 2011; 39:152-7. [PMID: 21411335 DOI: 10.1016/j.biologicals.2011.02.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 02/10/2011] [Accepted: 02/14/2011] [Indexed: 11/20/2022] Open
Abstract
Aino, Akabane and Chuzan viruses are arthropod-borne (arbo) viruses transmitted by blood-sucking insects like mosquitoes and Culicoides biting midges. These arbovirus infections are mainly associated with abortion, stillbirth and congenital defects in pregnant cattle, sheep and goats, which induces a considerable economic loss in livestock industry. The viruses seem to be widely distributed in Southeast Asia and Australia. As a control strategy, an inactivated trivalent vaccine against Aino, Akabane and Chuzan virus was developed by using binary ethylenimine or formalin as an inactivating agent. The newly developed trivalent vaccine is evaluated for its safety and immunogenicity in animals such as mice, guinea pigs and cattle. The immune responses were significantly detected within 2-weeks after second vaccination without any side effects. Since the field application of experimental vaccine also revealed increased antibodies in inoculated cattle, we demonstrated that these trivalent vaccines could be used as a vaccine to control the arboviral infections in ruminants.
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Kamata H, Inai K, Maeda K, Nishimura T, Arita S, Tsuda T, Sato M. Encephalomyelitis of cattle caused by Akabane virus in southern Japan in 2006. J Comp Pathol 2009; 140:187-93. [PMID: 19162275 DOI: 10.1016/j.jcpa.2008.12.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Revised: 11/21/2008] [Accepted: 12/01/2008] [Indexed: 11/18/2022]
Abstract
Six calves, aged between 55 days and 15 months, were presented between September and November 2006 with neurological signs including limb weakness and circling. Microscopical examination of the brain and spinal cord revealed the presence of non-suppurative encephalitis in all animals. Perivascular cuffing of lymphocytes and macrophages and diffuse gliosis was prominent in the cerebrum and degeneration and/or necrosis of neurons with vacuolation of the neuropil was present in the brainstem. Neuronal necrosis and neuronophagia were noted in the ventral horn of the spinal cord. The distribution of the lesions was closely related to the clinical signs displayed by each calf. Five calves presenting with astasia with low head carriage or torticollis had lesions throughout the central nervous system (CNS). The oldest calf displayed astasia caused by weakness of the "hindlimb" one word and had lesions largely restricted to the caudal spinal cord. Akabane virus (AKAV) antigens were detected immunohistochemically within neurons and axons in lesional tissue. Virus was not isolated from CNS tissue but the AKAV S gene was detected in this tissue from five calves by reverse transcriptase polymerase chain reaction (RT-PCR). It is suggested that AKAV infection is likely to have occurred during the early life period in the calves of this study.
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Affiliation(s)
- H Kamata
- Miyakonojo Livestock Hygiene Service Center, Miyazaki Prefecture, 4231-1 Omuta Takasaki Miyakonojo, Miyazaki 889-4505, Japan
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Kobayashi T, Yanase T, Yamakawa M, Kato T, Yoshida K, Tsuda T. Genetic diversity and reassortments among Akabane virus field isolates. Virus Res 2007; 130:162-71. [PMID: 17659802 DOI: 10.1016/j.virusres.2007.06.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Revised: 06/05/2007] [Accepted: 06/11/2007] [Indexed: 11/18/2022]
Abstract
Sequencing and phylogenetic analysis were carried out for 35 Akabane virus (AKAV) field isolates collected from Japan, Taiwan, Australia and Kenya, and for one Tinaroo virus (TINV). Of the three RNA segments, the M RNA segment encoding the glycoproteins that induce neutralization antibodies was the most variable among the isolates. The difference in the M RNA segments among Asian (Japanese and Taiwanese) isolates was not large (<12.3% nucleotide (nt) and <5.9% amino acid (aa) differences), rather than those between Asian and Australian isolates (13.4-14.9% nt and 6.2-8.2% aa difference). In phylogenetic trees, the Australian isolates form a separate branch from Asian isolates. All three RNA segments of the Kenyan isolate MP496 were genetically distant from those of the other AKAV field isolates. Although the S and L RNA segments of TINV, which is regarded as a strain of AKAV, was closely related to those of the Asian and Australian AKAV isolates, the M RNA was divergent that of the most distant AKAV isolate, MP496. Discrepancies among the phylogenetic trees of the S, M and L RNA segments indicate genomic reassortment events among AKAV field isolates.
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Affiliation(s)
- Takahiko Kobayashi
- Division 1, Second Production Department, the Chemo-Sero-Therapeutic Research Institute, 1-6-1 Okubo, Kumamoto 860-8568, Japan
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Abstract
Akabane and bovine ephemeral fever viruses are exotic to the American continent. Both viruses are spread by insect vectors, and each causes disease of varying severity in food-producing animals. However, there are few other similarities between the agents and the diseases that they cause. They do not share the same insect vectors, the mammalian host range is different, and the clinical manifestations of virus infection vary markedly. Akabane virus is a cause of severe congenital defects, but adult animals show no signs of infection. In contrast, bovine ephemeral fever virus causes a febrile illness affecting mainly mature animals. If introduced to North America, it is probable that there would be significant economic losses, at least until endemic virus transmission patterns were established. Subsequently, it is likely that there would be patterns of alternate disease outbreaks followed by interepidemic periods in which there is a minor clinical effect.
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Affiliation(s)
- Peter D Kirkland
- Virology Laboratory, Elizabeth Macarthur Agricultural Institute, NSW Agriculture, PMB 8, Camden, 2570 New South Wales, Australia.
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Uchida K, Murakami T, Sueyoshi M, Tsuda T, Inai K, Acorda JA, Yamaguchi R, Tateyama S. Detection of Akabane viral antigens in spontaneous lymphohistiocytic encephalomyelitis in cattle. J Vet Diagn Invest 2000; 12:518-24. [PMID: 11108451 DOI: 10.1177/104063870001200605] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A 5-month-old Japanese black bull calf and twenty-seven 1-27-day-old calves exhibiting neurological signs between August and October 1998 were examined. The bull calf exhibited rapid breathing, fever, hypersensitivity, and ataxia and was euthanized 4 days after the onset of symptoms. The 27 calves primarily exhibited ataxia, and 15 had arthrogryposis. Histological examination of the bull calf revealed perivascular infiltraction by mononuclear cells, diffuse to multifocal gliosis, and neuronal necrosis in the brain and spinal cord. Multiple malacic foci were found in the midbrain in 5 cases. In contrast, in the 15 calves necropsied in October, there were fewer inflammatory changes, but there was neuronal cell loss in the ventral horn and a decrease in myelinated axons in the lateral and ventral funiculi. Immunohistochemical examination using a rabbit antiserum against Akabane virus strain OBE-1 revealed a large amount of viral antigen in the degenerating neurons and glial cells of the bull calf, mainly in the spinal gray matter. Small amounts of viral antigen in swollen axons and a few glial cells were found in 5 of 27 calves. Thirteen of the 27 calves had high neutralization antibody titers against the Akabane virus, whereas there was no significant antibody titer in most of the calves necropsied during August. The present study revealed that viral antigen detection was very useful for the diagnosis of Akabane diseases in the 5-month-old bull calf that was suspected to be infected postnatally, while it had limited usefulness in the other young calves.
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Affiliation(s)
- K Uchida
- Department of Veterinary Pathology, Faculty of Agriculture, Miyazaki University, Japan
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Affiliation(s)
- M J Muller
- CSIRO Division of Tropical Animal Production Long Pocket Laboratories PMB 3, Indooroopilly Qld., Australia
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Abstract
Akabane virus, an arthropod-borne Bunyavirus, is the major cause of epizootics of congenital malformations in ruminants in Australia, Japan, Korea, and Israel, and is suspected to be a cause of sporadic outbreaks elsewhere. Blood-sucking insects, such as biting midges, transmit the virus horizontally to vertebrates. Climatic factors influence the seasonal activity and geographic range of the vector population and, therefore, occurrence of related disease. Inoculated ruminants seroconvert rapidly after a short subclinical viremia. Infection is of consequence only if ruminants are pregnant and not protected by adequate specific neutralizing antibodies. In naive pregnant animals, virus may spread hematogenously to replicate and persist in trophoblastic cells of placental cotyledons and subsequently invade the fetus. A distinct tropism for immature rapidly dividing cells of the fetal central nervous system and skeletal muscle results in direct virus-induced necrotizing encephalomyelitis and polymyositis. If fetuses survive, such injury may manifest as arthrogryposis, hydranencephaly, porencephaly, microencephaly, hydrocephalus, or encephalomyelitis at term. The earlier in gestation that fetal infection occurs, the more severe the lesions, reflecting the large population of vulnerable cells and lack of fetal immunocompetency at earlier stages of pregnancy. Injury during the period of critical cell migration and differentiation in organogenesis may substantially disrupt structural development in target organs. Late gestational infections cause nonsuppurative inflammation in the brain and spinal cord, premature birth, or fetal death with stillbirth or abortion. Affected neonates are nonviable. Control is by vaccination but is not always justified economically. Akabane viral infections must be differentiated from infections with other teratogenic viruses (including related Bunyaviruses), inherited conditions, and maternal intoxications. Diagnosis is made by serology and viral isolation.
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Affiliation(s)
- J A Charles
- Veterinary Pathology Services Pty Ltd, Sydney, Australia
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