• 생명과학회지
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• 제33권8호
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• pp.605-611
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• 2023

최근에 재조합 H7Nx 인플루엔자 바이러스가 산발적으로 인체 감염 사례가 보고되고 있으며 이러한 바이러스는 조류 종으로부터 지속적으로 분리되고있다. 본 연구에서는 조류에서 유래된 H7N1 인플루엔자 바이러스를 분리하여 A/wild bird/South Korea/sw-anu/2023로 명명하였고, 전장유전체 분석과 분자적 특성을 분석하였다. 계통발생학적 분석 결과 A/wild bird/South Korea/sw-anu/2023는 유라시아 혈통에 속하는 H7N1 인플루엔자 바이러스로 확인되었다. A/wild bird/South Korea/sw-anu/2023 바이러스의 polymerase basic 1(PB)2, PB1, polymerase acidic (PA), nucleoprotein (NP) 유전자는 야생 조류에서 분리되었던 조류 인플루엔자 바이러스유전자와 밀접한 관련이 있는 것으로 밝혀졌으며, hemagglutinin (HA), neuraminidase (NA), matrix (M), nonstructural (NS) 유전자는 집오리에서 분리되었던 조류 인플루엔자 바이러스와 유사하였다. 이러한 결과는 동아시아-호주 이동 경로를 따라 이동하는 야생 조류들 사이에서 새롭게 유전자가 재배열된 재조합 H7N1 조류 인플루엔자 바이러스가 순환되고 있음을 시사하고 있다. 따라서, H7Nx 인플루엔자 바이러스는 전 세계적으로 순환하며, 돌연변이된 H7N1 조류 인플루엔자 바이러스는 인간을 감염시킬 수 있으므로 야생 조류 및 가금류에서 H7N1 조류 인플루엔자 바이러스의 지속적인 감시가 필요할 것이다.

• Journal of Veterinary Science
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• 제22권2호
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• pp.21.1-21.6
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• 2021

In this study, we describe the isolation and characterization of previously unreported Y280-lineage H9N2 viruses from two live bird markets in Korea in June 2020. Genetic analysis revealed that they were distinct from previous H9N2 viruses circulating in Korea and had highest homology to A/chicken/Shandong/1844/2019(H9N2) viruses. Their genetic constellation showed they belonged to genotype S, which is the predominant genotype in China since 2010, where genotype S viruses have infected humans and acted as internal gene donors to H5 and H7 zoonotic influenza viruses. Active surveillance and control measures need to be enhanced to protect the poultry industry and public health.

• 대한수의학회지
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• 제53권4호
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• pp.193-197
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• 2013

Avian influenza viruses (AIV) have been isolated from a wide range of domestic and wild birds. Wild birds, predominantly ducks, geese and gulls form the reservoir of AIV in nature. The viruses in wild bird populations are a potential source of widespread infections in poultry. Active surveillance for AIV infection provides information regarding AIV distribution, and global AIV surveillance can play a key role in the early recognition of highly pathogenic avian influenza (HPAI). Since 2003 in Korea, there have been four H5N1 HPAI outbreaks caused by clade 2.5, 2.2 and 2.3.2. Therefore, improvement of AIV surveillance strategy is required to detect HPAI viruses effectively. This article deals with the major events establishing the role of wild birds in the natural history of influenza in Korea. We highlighted the need for continuous surveillance in wild birds and characterization of these viruses to understand AIV epidemiology and host ecology in Korea.

• Journal of Veterinary Science
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• 제19권6호
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• pp.850-854
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• 2018

Novel H5N6 highly pathogenic avian influenza viruses (HPAIVs) were isolated from duck farms and migratory bird habitats in South Korea in November to December 2017. Genetic analysis demonstrated that at least two genotypes of H5N6 were generated through reassortment between clade 2.3.4.4 H5N8 HPAIVs and Eurasian low pathogenic avian influenza virus in migratory birds in late 2017, suggesting frequent reassortment of clade 2.3.4.4 H5 HPAIVs and highlighting the need for systematic surveillance in Eurasian breeding grounds.

• Journal of Veterinary Science
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• 제21권4호
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• pp.56.1-56.13
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• 2020

Background: The live bird market (LBM) plays an important role in the dynamic evolution of the avian influenza H5N1 virus. Objectives: The main objective of this study was to monitor the genetic diversity of the H5N1 viruses in LBMs in Indonesia. Methods: Therefore, the disease surveillance was conducted in the area of Banten, West Java, Central Java, East Java, and Jakarta Province, Indonesia from 2014 to 2019. Subsequently, the genetic characterization of the H5N1 viruses was performed by sequencing all 8 segments of the viral genome. Results: As a result, the H5N1 viruses were detected in most of LBMs in both bird' cloacal and environmental samples, in which about 35% of all samples were positive for influenza A and, subsequently, about 52% of these samples were positive for H5 subtyping. Based on the genetic analyses of 14 viruses isolated from LBMs, genetic diversities of the H5N1 viruses were identified including clades 2.1.3 and 2.3.2 as typical predominant groups as well as reassortant viruses between these 2 clades. Conclusions: As a consequence, zoonotic transmission to humans in the market could be occurred from the exposure of infected birds and/or contaminated environments. Moreover, new virus variants could emerge from the LBM environment. Therefore, improving pandemic preparedness raised great concerns related to the zoonotic aspect of new influenza variants because of its high adaptivity and efficiency for human infection.

• 대한수의학회지
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• 제64권2호
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• pp.13.1-13.6
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• 2024

Avian influenza A viruses (IAVs) present significant threats to both animal and human health through their potential for cross-species transmission and global spread. Clade 2.3.4.4 H5Nx highly pathogenic avian IAVs initially emerged in East Asia between 2013 and 2014. Since then, they have spread to Europe, Africa, and America via migratory bird flyways. However, beyond viral transmission primarily facilitated by migratory birds, the potential involvement of other intermediate factors for virus transmission remains poorly investigated. This study aimed to investigate the role of wild rodents as intermediary hosts in the ecology of avian IAVs in Gyeonggi province, South Korea. By capturing and analyzing 189 wild rodents near poultry farms and migratory bird habitats in 2013 and 2014 and employing serological assays and virus isolation techniques, we found no evidence of IAV infection among these populations. Our results suggest that wild rodents may not significantly contribute to the transmission dynamics of IAVs within these regions.

• 한국환경보건학회지
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• 제33권5호
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• pp.434-440
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• 2007

The livestocks are sometimes infected with pathogenic microorganisms such as bird influenza, brucellosis, pig cholerae, and salmonella. However, it is difficult to predict the outcome of these diseases because the livestocks are mostly raised in the rural areas. Efficient systems for detecting and alerting the onset of livestock diseases are urgently required. In these studies, the fluorescent analysis method, luminescent analysis method, and frequently used gene amplification method (polymerase chain reaction) have been developed in order to detect the pathogenic microbes in the early stages of disease progression. By using these developed systems, damages due to the livestock diseases induced by microbes can be minimized. If we can detect livestock diseases in the early stage, the costs for diagnosis and treatment will be reduced, and the livestock can be quickly recovered.

• Journal of Multimedia Information System
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• 제5권2호
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• pp.91-98
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• 2018

We devised a bird-borne transceiver unit for S-band packet radio communications based on the CC2500 transceiver, a device manufactured by Texas Instruments (TI). Our assessments determined the optimal parameters needed to achieve successful bird-to-center communication over a distance of 18 km and bird-to-bird communication over a distance of 200 m. These parameters included optimal modulation methods, transmission rates, and antennas. We equipped the transceiver unit with a modified dipole antenna (collinear antenna), which we tested in a 10 m anechoic chamber. Our experimental assessments and circuit design review identified the following parameters: 2FSK modulation method; 14.28 kHz frequency shift; 101.56 kHz IF reception bandwidth; and Manchester encoding (+). Our assessments showed bird-to-bird communications could be achieved over a distance of 200 m assuming MSK, FEC (+), and 500 kbps. Following tests by an official body, we obtained 28 sets of a type approval license for 2.4 GHz. In cooperation with the Yamashina Institute for Ornithology, we attempted to tag and release six or more swans. This unit gives us the ability to obtain vital data on swans. We expect this data to provide significant benefits, including clues on improving screening for infected individuals.

• 한국동물위생학회지
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• 제45권4호
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• pp.285-292
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• 2022

Avian influenza viruses (AIVs) cause contagious diseases and have the potential to infect not only birds but also mammals. Wild birds are the natural reservoir of AIVs and spread them worldwide while migrating. Here we collected active AIV surveillance data from wild bird habitats during the 2019 to 2022 winter seasons (from September to March of the following year) in South Korea. We isolated 97 AIVs from a total of 7,590 fecal samples and found the yearly prevalence of AIVs was 0.83, 1.48, and 1.27, respectively. The prevalence of AIVs were generally higher from September to November. These findings demonstrate that a high number of wild birds that carry AIVs migrate into South Korea during the autumn season. The highest virus numbers were isolated from the species Anas platyrhynchos (72%; n=70), followed by Anas poecilorhyncha (15.4%; n=15), suggesting that each is an important host for these pathogens. Twenty-five hemagglutinin-neuraminidase subtypes were isolated, and all AIVs except the H5N8 subtype were found to be low-pathogenic avian influenza viruses (LPAIVs). Active surveillance of AIVs in wild birds could benefit public health because it could help to estimate their risk for introduction into animals and humans. Moreover, considering that 132 cases of human AIV infections have been reported worldwide within the last 5 years, active surveillance of AIVs is necessary to avoid outbreaks.

• 대한수의학회지
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• 제52권4호
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• pp.239-252
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• 2012

The circulation and infection of avian influenza virus (AIV) in zoos and backyard flocks has not been systematically investigated. In the present study, we surveyed the birds including those in live bird markets (LBMs) and evaluated co-circulation of AIVs among them. Overall, 26 H9N2 AIVs and one H6N2 AIV were isolated from backyard flocks and LBMs, but no AIVs were isolated from zoo birds. Genetic analysis of the HA and NA genes indicated that most of the H9N2 AIVs showed higher similarities to AIVs circulating in domestic poultry than to those in wild birds, while the H6N2 AIV isolate from an LBM did to AIVs circulating in migratory wild birds. In serological tests, 15% (391/2619) of the collected sera tested positive for AIVs by competitive-ELISA. Among them, 34% (131/391) of the sera tested positive for AIV H9 antigen by HI test, but only one zoo sample was H9 positive. Although AIVs were not isolated from zoo birds, the serological results indicated that infection of AIVs might occur in zoos. It was also confirmed that H9N2 AIVs continue to circulate and evolve between backyard flocks and LBMs. Therefore, continuous surveillance and monitoring of these flocks should be conducted to control further epidemics.