• 한국동물위생학회지
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• 제39권4호
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• pp.267-270
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• 2016

We determined the nationwide seroprevalence of hepatitis E virus (HEV) infection in the wild boar population in Korea. Enzyme-linked immunosorbent assay (ELISA) results showed that 42% of the 528 wild boars that were hunted between 2013 and 2014 were anti-HEV antibody positive. Furthermore, all Korean provinces showed an HEV seroprevalence between 9.8% and 51.1%, suggesting that wild boar HEV infection occurs throughout the country. Importantly, infected wild boar could act as a potential reservoir for HEV and could aid transmission to other animals and humans.

• Journal of Veterinary Science
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• 제19권6호
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• pp.788-797
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• 2018

In many countries, vaccines are used for the prevention of foot-and-mouth disease (FMD). However, because there is no protection against FMD immediately after vaccination, research and development on antiviral agents is being conducted to induce protection until immunological competence is produced. This study tested whether well-known chemicals used as RNA virus treatment agents had inhibitory effects on FMD viruses (FMDVs) and demonstrated that ribavirin showed antiviral effects against FMDV in vitro/in vivo. In addition, it was observed that combining the administration of the antiviral agents orally and complementary therapy with vaccines synergistically enhanced antiviral activity and preserved the survival rate and body weight in the experimental animals. Antiviral agents mixed with an adjuvant were inoculated intramuscularly along with the vaccines, thereby inhibiting virus replication after injection and verifying that it was possible to induce early protection against viral infection prior to immunity being achieved through the vaccine. Finally, pigs treated with antiviral agents and vaccines showed no clinical signs and had low virus excretion. Based on these results, it is expected that this combined approach could be a therapeutic and preventive treatment for early protection against FMD.

• 한국미생물·생명공학회지
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• 제46권3호
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• pp.269-276
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• 2018

Rabies virus (RABV)-specific antibodies in animals and humans are measured using standard methods such as fluorescent antibody virus neutralization (FAVN) tests and rapid fluorescent focus inhibition tests, which are based on cell culture systems. An alternative assay that is safe and easy to perform is required for rapid sero-surveillance following mass vaccination of animals. Two purified monoclonal antibodies (4G36 and B2H17) against RABV were selected as capture and detection antibodies, respectively. A genetically modified RABV, the ERAGS strain, was propagated and concentrated by polyethylene glycol precipitation. Optimal conditions for the RABV antigen, antibodies, and serum dilution for a blocking enzymelinked immune sorbent assay (B-ELISA) were established. We evaluated the sensitivity, specificity, and accuracy of the B-ELISA using serum samples from 138 dogs, 71 raccoon dogs, and 25 cats. The B-ELISA showed a diagnostic sensitivity of 95.8-96.3%, specificity of 91.3-100%, and accuracy of 96.0-97.2% compared to the FAVN test. These results suggest that the B-ELISA is useful for sero-surveillance of RABV in dogs, raccoon dogs, and cats.

• 식물병연구
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• 제15권1호
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• pp.8-12
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• 2009

Virus disease surveys of strawberries cultivated and preserved as germplasm resources in Korea was conducted during 2007-2008. Virus detection was conducted by RT-PCR using total RNAs extracted from strawberry samples. We detected the infection with Strawberry mild yellow edge virus (SMYEV), Strawberry mottle virus (SMoV), Strawberry vein banding virus (SVBV) and Strawberry pallidosis associated virus (SPaV) while no infection with Strawberry crinkle virus (SCV), Strawberry necrotic shock virus (SNSV), Strawberry latent ring spot virus (SLRSV) and Arabis mosaic virus (ArMV) was observed. The infection rate of virus disease on 4 cultivars including Seolhyang, Maehyang, Gumhyang, and Dahong, bred in Korea, was 0.1, 1.9, 0, and 0%, respectively. Surprisingly, however, cultivar Red Peal introduced from Japan in 1997 revealed 48.3% virus infection rate. SMYEV, SMoV and SPaV were also identified in strawberries growing in the farm fields of Korea. In the field, however, SMYEV was the most predominant virus (97.4%) among those 3 identified viruses. SVBV was detected only in strawberry kept as a germplasm.

• 한국동물위생학회지
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• 제36권3호
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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.

• 식물병연구
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• 제8권2호
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• pp.78-83
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• 2002

Tobacco diseases have not been recorded until 1900s in Korea, where tobacco plants were introduced at early 1700s. Practical researches on the disease have been conducted since mid 1960s. Major ten tobacco diseases were mosaic caused by tobacco mosaic virus·potato virus Y·cucumber mosaic virus, bacterial wilt, hollow stalk, wild fire caused by angular leaf spot strain, black shank, brown spot, powdery mildew and fusarium wilt. But their annual occurrences were varied according to changes of tobacco varieties and their cultivating practices. As no useful chemicals, several biological tactics have been developed to control the viral or bacterial diseases that give significant economic damages on sustainable crop yield, but not practicable to field farming condition yet. Transgenic tobacco plants containing foreign disease resistant genes have been developed by current bio-technology, but not released to farmers yet. Though some disease-resistant tobacco varieties have been developed by the conventional breeding technology and currently used by farmers, their disease controlling efficacy have been diminished by occurrence of the new strain or race. Future research on tobacco diseases has been focused on technical development to produce high quality tobacco with less production cost, which leads Korean tobacco industry to keep its competence against foreign industry and decreasing overall market.

• 한국응용곤충학회지
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• 제15권2호
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• pp.61-68
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• 1976

광교, 동북태, 강림, 육우3호, 은대두등과 같은 대리장려품종이 바이러스에 의하여 심하게 이병되었다. 이 병은 주로 모자익병의 발생이 많은 강원, 경기지방에서 발병이 심하였으나 모자익병이 심하지 않은 전남 등 남부지방에서도 발병되고 있다. 병징으로 보아 tobacco ringspot virus에 의한 대두의 피해와 유사한 것으로 보였으나 지표식물검정과 혈청검정에 의하여 조사한 결과 모두 부정적이었으며 대두품종에 따른 이병정도의 상이, 품종과 접종원에 의한 병징의 변이가 많았다. 이병주에서 분리되는 병징형은 Mottling과 necrosis였으며 지금까지의 연구결과 이 대두병해는 모자익바이러스(SMV)의 계통 내지는 tobacco ringspot virus 이외의 두류바이러스의 복각감염에 의한 것으로 생각할 수 있으나 SMV의 계통에 의한 피해일 가능성이 더욱 유력시되고 있다.

• Journal of Veterinary Science
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• 제21권2호
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• pp.22.1-22.9
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• 2020

Rabid raccoon dogs (Nyctereutes procyonoides koreensis) have been responsible for animal rabies in South Korea since the 1990s. A recombinant rabies vaccine strain, designated as ERAGS, was constructed for use as a bait vaccine. Therefore, new means of differentiating ERAGS from other rabies virus (RABV) strains will be required in biological manufacturing and diagnostic service centers. In this study, we designed two specific primer sets for differentiation between ERAGS and other RABVs based on mutation in the RABV glycoprotein gene. Polymerase chain reaction analysis of the glycoprotein gene revealed two DNA bands of 383 bp and 583 bp in the ERAGS strain but a single DNA band of 383 bp in the field strains. The detection limits of multiplex reverse transcription polymerase chain reaction (RT-PCR) were 80 and 8 FAID₅₀/reaction for the ERAGS and Evelyn-Rokitnicki-Abelseth strains, respectively. No cross-reactions were detected in the non-RABV reference viruses, including canine distemper virus, parvovirus, canine adenovirus type 1 and 2, and parainfluenza virus. The results of multiplex RT-PCR were 100% consistent with those of the fluorescent antibody test. Therefore, one-step multiplex RT-PCR is likely useful for differentiation between RABVs with and those without mutation at position 333 of the RABV glycoprotein gene.

• 대한수의학회지
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• 제62권3호
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• pp.19.1-19.6
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• 2022

Japanese encephalitis virus (JEV) and Akabane virus (AKAV) are mosquito-borne viruses that cause encephalitis and reproductive disorders in horses and cattle, respectively. There is no treatment for JEV or AKAV infections in animals. Therefore, we evaluated the antiviral activity of 18-mer amphipathic peptides in the 1b-4/21-C series on JEV and AKAV using Vero cells in vitro and evaluated their effects on JEV in mice. Of 6 peptides, 1b-4/21-C12 had the lowest IC₅₀ of 0.313 against JEV and its use as an antiviral against JEV and AKAV was examined. The IC₅₀ of 1b-4/21-C12 against JEV and AKAV was 0.78 and 1.14 µM, respectively. Mice treated with 5 or 2 mg/kg of 1b-4/21-C12 had 32% and 16% survival rates, respectively, and the surviving mice treated with 1b-4/21-C12 began to gain weight beginning 8 days post challenge with the virulent Nakayama strain. Moreover, 20 µM 1b-4/21-C peptide had no cytotoxic effects on Vero cells. Our in vitro and in vivo results indicate that 1b-4/21-C12 has antiviral activity against enveloped JEV and AKAV and might be useful as a therapeutic substance.

• The Plant Pathology Journal
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• 제33권3호
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• pp.288-295
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• 2017

Fig mosaic disease (FMD) is a viral disease that spreads in all Tunisian fig (Ficus carica L.) orchards. RT-PCR technique was applied to leaf samples of 29 fig accessions of 15 fig varieties from the fig germplasm collection of High Agronomic Institute (I.S.A) of ChattMariem, to detect viruses associated to FMD. Analysis results show that 65.5% of the accessions (19/29) and 80.0% (12/15) of the fig varieties are infected by FMD-associated viruses. From all fig accessions, 41.4% of them are with single infection (one virus) and 24.1% are with multi-infections (2 virus and more). Viruses infecting fig leaf samples are Fig mosaic virus (FMV) (20.7%), Fig milde-mottle-associated virus (FMMaV) (17.25%), Fig fleck associated virus (FFkaV) (3.45%), and Fig cryptic virus (FCV) (55.17%). A reliable protocol for FCV and FMMaV elimination from 4 local fig varieties Zidi (ZDI), Soltani (SNI), Bither Abiadh (BA), and Assafri (ASF) via in vitro culture of 3 meristem sizes was established and optimized. With this protocol, global sanitation rates of 79.46%, 65.55%, 68.75%, and 70.83% respectively for ZDI, SNI, BA, and ASF are achieved. For all sanitized varieties, the effectiveness of meristem culture for the elimination of FCV and FMMaV viruses was related to meristem size. Meristem size 0.5 mm provides the highest sanitation rates ranging from 70% to 90%.