• Journal of Veterinary Clinics
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• v.20 no.3
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• pp.427-430
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• 2003

Akabane virus is a cause of severe congenital defects, but adult animals show no signs of infection. In this study, congenital abnormalitis associated with Akabane virus infection in Korean native goat. The prevalence of serum neutralizing antibodies to Akabane virus in goat population was investigated, indicating that approximately 30% of goats in Korea were seropositive(36/120). The mother goats have the highest titers of neutralizing antibodies, as 1:128. And also there showed seropositive of Akabane virus in newborn fetus fluids. The necropsy results of newborn fetus visceral organs were appeared normal. These findings provide that Akabane virus is the ethiological agent of congenital abnormalitis and stillbirth. Our results suggest that goat in natural situations are part of the Akabane virus transmission cycle.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.42-48
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• 2000

Akabane disease is transmitted through mosquitoes in cattle, sheep and goats. It shows congenital abnormalities including encephalomyetitis, hydranencephaly, neurogenic arthrogryposis, and deformed neonatal calves. Akabane viruses, 93FMX and K-9 strain, were isolated from fetal matrix of aborted cow and blood of healthy cow, respectively. S gene sequences of 93FMX and K-9 showed 100% homology with that of OBE-1 strain isolated in Japan. Based upon our sequencing data, we synthesized specific primers for PCR diagnosis. Using these primers, we were able to amplify the S gene of Akabane virus not only from the culture fluid of Vero cells but also from the brain tissue of suckling mouse inoculated with, Akabane virus. These PCR products were confirmed by Southern blot hybridization. Not only the sensitivity of PCR test was high enough to detect the viruses of $10^{1.0}TCID_{50}/ml$, but also the time for diagnosis was significantly shorter than that of the virus isolation by tissue culture method. This method was also effective for the detection of Akabane virus in the cerebrum of fetus. RT-PCR method may be used for a useful diagnostic test of the clinical cases of Akabane disease.

• Korean Journal of Veterinary Service
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• v.17 no.1
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• pp.1-8
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• 1994

To investigate serum neutralizing antibodies against Bovine ephemeral fever (BEF) virus, Akabane virus and Ibaraki virus in southern area of Chungnam province, Holstein sera were collected from April-May(269 heads /37 farms) and October-November (226 heads /35 farms), 1993. The results were summarized as follows ; 1. Bovine ephemeral fever.-antibody positive rates to BEF virus were 46.1% (124 heads /269 Holstein) in April-May and 53.9%(122 heads /226 Holstein) in October-November. 2. Akabane disease.-antibody positive rates to Akabne virus were 34.2％(92 heads /269 holstein) in April-May and 51.3%(116 heads /226 Holstein) in October-Novermber. 3. Ibaraki disease.-antibody positive rates to Ibaraki virus were 57.6%(155 heads /269 Holstein) in April -May and 38.5%(87 heads /226 Holstein) in October-November.

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.93-102
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• 2000

In this experiment, we studied the sero-positive rate of akabane virus in cattle from Jeju-do and analyzed the seroepidemiological features. In an analysis of 1,051 samples, the positive rate for neutralizing antibody in sera collected in nine regions on Jeju-do was 56.7%. The rate varied with the region. The positive rate was 69.6% in Aewol, 63.1% in Jeju city, 54.4% in Anduck, 51.0% in Hallim, 69.8% in Jocheun, 47.6% in Pyosun, 40% in Daejeong, 30.0% in Harkyung, 71.6% in Namwon, 24.5% in Sungsan, 133.,3% in Seokypo and 44.5% in Gujwa, respectively The rate also depended on the age of the cattle. The positive rate was 67.2% in calves 0- to 12-month old, 48.3% in cattle 13- to 24-month old, 65.4% in cattle 25- to 36-month old, and 65.4% in cattle more than ,B7 months old. To isolate the virus from calves with malformations including arthrogryposis and hydranencephaly, cerebral homogenates were inoculated into Vero cells, which were determined for cytopathic effect (CPE). Vero cells with CPE were examined for Akabane virus using an electron microscope (EM) and indirect immunofluorescent antibody test (EM). Typical virus particles with a width of 90-130nm and specific immunofluorescence in the cytoplasm of infected cells were sought for identification.

• Korean Journal of Veterinary Research
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• v.55 no.4
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• pp.227-232
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• 2015

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.

• Korean Journal of Veterinary Service
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• v.14 no.1
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• pp.19-26
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• 1991

A considerably high rate of abnormal deliveries of unknown etiology was observed among dairy cattles from November 1988 to February 1989 and Korean native tattles from January to April 1990. The abnormal deliveries consisted of abortions, stillbirths and calf deformities refers to as congenital arthrogryposis hydranencephaly (AH )syndrome. In order to know the level of Akabane antibody of dairy cattle raised in Kyungbuk province, serum neutralization test was conducted with Akabane virus(OBE-1 strain) and HmLu(Hamster lung) cell line. The results were summarized as follows. 1. During 4 months(Nov. 1988-Feb. 1989), abortion (3 heads), stillbirth(1 head) and congenital abnormalities(13 heads) of newborn were occurred in 17 dairy cattles raised in Kyungbuk province. 2. During 4 months(Jan.-Apr.1990), stillbirth(2 heads) and congenital deformities (13 heads) of newborn were occurred in 15 Korean native tattles raised in Kyungbuk province. 3. In Fev, and Apr. 1990, 1,005 dairy cattles at 99 farms were investigated on the actual condition of possessing Akabane antibody. The result was that 1,000 heads (99.9%) in 1,005 dairy cattles reacted as positive condition in Akahane antibody. The antibody titer was from 4 to over 256. 4. 189 heads (18.8%) of 1,005 dairy cattles werw below antibody titer 8 and 816 heads (81.2%) were over 16. 5. Akabane antibody titer of east coast legions(Pohang Yeongil etc) was all over 16, that of internal legions (Yeongiu, Andong. etc) was relatively low, The result suggest that the vaccination for Akabane disease will be unnecessary for the time being because of possessing higher antibody titer reaction except the newly introduced cattle and Akabane virus was widely disseminated in kyungbuk province during the summer months in 1987 or 1988.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.61-66
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• 2008

Akabane disease is caused by an arthropod-borne viral pathogen and leads to congenital abnormalities of the central nervous system in infected ruminants. One isolate, KV0505, showed cytopathic effect in Vero cells. The KV0505 isolate was obtained from plasma, which was collected from a cattle raised on Jeju Island in May 2005. Jeju Island is located near the southern part of the Korean peninsula. The isolate was confirmed as Akabane virus (AKAV) by immunofluorescence assay using AKAV specific monoclonal antibodies and reverse transcription polymerase chain reaction (RTPCR). Suckling mice inoculated with the isolate showed signs of paralysis and died within 10 days postinoculation. Comparisons of the KV0505 N gene sequence with 39 other known AKAV strains revealed nucleotide homologies ranging from 83.6% (MP496 strain) to 99.7% (M171 strain). When compared with the K-9 strain, which was isolated from a cow in Korea in 1994, the nucleotide sequence homology with the N gene was 99.7%. Thus, genes of the KV0505 isolate were closely related to those of the M171 strain, which were clustered into the Ic group of AKAV.

• Korean Journal of Veterinary Service
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• v.29 no.3
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• pp.365-376
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• 2006

To identify immune response of leukocytes in peripheral blood of cattle vaccinated with an attenuated live Akabane virus vaccine, leukocytes were reacted with monoclonal antibodies which are specific to bovine lymphocyte surface antigens and assayed by the flow cytometry. Serum neutralizing (SN) test was used to measure antibody titers after vaccination, SN antibody was appeared to 7 days post-vaccination (PV) and 2-8 antibody titers were observed in 14 days PV. Proportion of $CD8^-$ MHC $class II^+$ expressing cells were rapidly increased at 3 days PV. $CD8^+$ MHC $class II^-$ cells were increased at 7 days PV. $CD4^+CD8^-,\;WC^+CD4^-,\;CD4^+CD8^+,\;WC1^-CD4^+, \;WC1^-CD8^+$, and $CD4^-CD8^+$ cells were highly increased at 3, 3, 7, 7, 14, 14 days PV, respectively.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.151-155
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• 2013

Since a large number of Akabane and bovine ephemeral fever (BEF) infection occurred in the southern part of Korea in 2010, recent information about seroprevalence of Akabane virus (AKAV) and bovine ephemeral fever virus (BEFV) has been required for preventing both diseases. In this study, serological assay against AKAV and BEFV using virus neutralization assay was conducted using 1,743 bovine sera collected from Namwon, Miryang, Yeongju and Uljin which located in Southern part of Korea from March to May in 2012. The overall seropositive rates for AKAV and BEFV were found to be 49.8% and 1.2%, respectively. The regional distribution of seroprevalence for AKAV ranged from 18.1% to 63.7%. Seroprevalences of AKAV were 63.7% in Miryang, 62.3% in Uljin, 50.7% in Namwon, and 18.1% in Yeongju. The seropositive rates for AKAV in southern part of Korea were higher than the annual average at the national level. On the other hand, seropositive rates of BEFV in four regions were from 0.3 to 3.1%. In detail, regional seroprevalences were 3.1% in Miryang, 2.0% in Uljin, and 1.7% in Yeongju, and 0.3% in Namwon. Even only one year after massive outbreaks, overall seropositive rates were very low, similar to the annual average at the nation level. This result indicates that many number of cattle infected with BEFV may be replaced by new born calf or cattle in farm may not be immunized with vaccines. To prevent another epidemic, a national wide warning should be issued and more aggressive control measure must be implied. Recent global warming phenomenon could lead to more vigorous activity of haematophagous vectors and it is possible that arboviral diseases such as AKAV and BEFV are increased. Therefore, continuous sero-monitoring and extensive vaccination combined with control of haematophagous vectors are important to effectively prevent and control diseases caused by AKAV and BEFV.

• Journal of Veterinary Clinics
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• v.15 no.1
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• pp.100-103
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• 1998

아까바네 바이러스로 인하여 유산된 태아의 뇌조직으로부터 '아까바네 바이러스 항원을 면역학적으로 검출하는 기법을 확립하였다. 아까바네 바이러스로 유산된 태아의 뇌는 조 직이 거의 손실되거나 유약하여 부검 즉시 포르말린 등에 보존하여야 하므로, 포르말린에 보존 된 뇌조직을 절편 하여 파라핀으로 포매된 조직표본으로부터 immunohistochemistry 방법으로 아까바네 바이러스 특이 항원을 검출하였다. 또한 이들 조직으로부터 직접 마우스 뇌내 접종과 조직배양내 바이러스 분리를 통하여 immunohistochemistry 법의 항원 검출 효율이 높음을 확 인하였다. 유산된 태아의 뇌조직에서 단크론 항체를 이용한 항원 검출 실험에서 세포의 세포질 내에서 아까바네 특이 항원이 검출되었고 hematoxylin-rosin 대조 염색으로 항원을 특이적으로 구분하여 진단할 수 있었다. 바이러스에 감염된 세포는 조직학적으로 변성이 심한 부위에서 다 수 관찰되었고 맥관계에 가까운 세포에서도 독립적으로 감염된 세포가 관찰되었다.