• 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.

• 생명과학회지
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• 제28권8호
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• pp.962-968
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• 2018

A형 인플루엔자바이러스는 야생조류에 존재하며, 사람, 돼지, 가금 및 다른 포유류등 다양한 숙주를 감염한다. 본 연구에서는, 2016년 한국 서쪽의 철새도래지에서 채취한 철새 분변에서 재조합된 새로운 H7N7 조류인플루엔자를 분리하였으며 이 바이러스의 8개 유전자를 분석하였다. 분리된 A/waterfowl/Korea/S017/2016(H7N7) 바이러스의 유전자 분석 결과 이 바이러스는 야생조류 및 가금 오리에서 유래한 조류인플루엔자로 구성된 재조합된 유전자를 가지고 있었다. 계통 분석결과 이 바이러스는 유럽과 아시아계에 속하였다. 조류인플루엔자 바이러스가 계속 진화를 하고 H7 형 조류인플루엔자는 고 병원성 조류인플루엔자로 변하여 사람과 동물에게 커다란 위협이 될 수 있기에 계속 된 역학조사가 필요하다.

• 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.

• 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.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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• pp.1130-1135
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• 2009

조류인플루엔자는 닭이나 오리와 같은 가금류 또는 야생조류에서 생기는 바이러스의 하나로, 농장에 큰 피해를 줄 뿐 아니라 인체에 치명적 영향을 줄 수 있다. 특히 조류인플루엔자의 주요 발생원이 철새로 추정되는 상황에서 이에 대한 예찰활동은 중요하다. 철새가 텃새에게 조류인플루엔자를 전염시키면 이로 인해 국내 가금류에게 2차 전염을 유발할 확률이 높기 때문이다. 따라서 본 연구는 겨울철 국내에 유입되는 철새의 AI 전파 현상을 시스템다이나믹스를 이용하여 모델링함으로써 예찰활동에 대한 시사점을 도출하였다.

• 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.

• 한국가금학회지
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• 제31권2호
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• pp.109-118
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• 2004

Avian influenza(AI) is an epizootic disease of variable severity caused by type A influenza viruses of the orthomyxovirus group. Chickens were the most frequently affected avian species with AI viruses. There were many outbreaks of fowl plague, now known as highly pathogenic AI(HP AI), throughout the world since Perroncito described the fowl plague in 1978 in Italy. In recent years HPAI viruses of different serotypes such as H5, H7 and H9 has been isolated from humans on several occasions either related with outbreak of HPAI in birds or not. In 1997, one of the most noteworthy events in AI history was the human mortality with H5N1 HPAI virus infection in Hong Kong. Six persons of total 18 persons with clinical signs of influenza were died. Recently the human cases with mortality related with HP AI outbreaks in poultry industry has been increased such as outbreaks of HP AI throughout Asia countries including Korea, Japan, China, Vietnam, Thailand and others in 2003. Although these outbreaks revealed the capable of spreading from birds to human, the capability for transmission between people was not clear. Therefore, this report will review the possibility of HP AI infection in human associated with HPAI outbreak in poultry industry.

• Journal of Multimedia Information System
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• 제6권4호
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• pp.293-302
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• 2019

In the past, there was a theory that influenza wasn't transmitted directly from birds but was infected to humans via swains. Recently, molecular level research has progressed, and it was confirmed that the avian influenza virus can directly infected to human lung and intestinal epithelial cells. Three pandemicsin the past 100 years were also infected to humans directly from birds. In view of such scientific background, we are developing a method for screening sick birds by monitoring the physiological characteristics of birds in a contactless manner with sensors. Here, the movement of respiratory muscles and abdominal muscles under autonomic innervation was monitored using a magnet and Hall sensor sewn on the thoracic wall, and other multimedia devices. This paper presents and discusses the results of experiments involving continuous periodic noise discovered during flight experiments with a data logger mounted on a Japanese pheasant from 2012 to 2015. A brief summary is given as the below: 1. Magnet and Hall sensor sewn to the left and right chest walls, bipolar electrocardiograms between the thoracic walls, posterior thoracic air sac pressure, angular velocity sensors sewn on the back and hips, and optical reflection of LEDs (blue and green) from the skin of the hips allow observation of periodic vibrations(fasciculations) in the waves. No such analysis has been reported before. 2. These fasciculations are presumed to be derived from muscle to maintain and control air sac pressure. 3. Since each muscle fiber is spatially Gaussian distributed from the sympathetic nerve, the envelope is assumed to plot a Gaussian curve. 4. Since avian trunk muscles contract periodically at all time, we assume that the sympathetic nerve dominates in their control. 5. The technique of sewing a magnet to the thoracic wall and measuring the strength of the magnetic field with a Hall sensor can be applied to screen for early stage of avian influenza, with a sensor attached to the chicken enclosure.

• 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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• 제23권3호
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• pp.36.1-36.14
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• 2022

Background: Since 2003, the H5 highly pathogenic avian influenza (HPAI) subtype has caused massive economic losses in the poultry industry in South Korea. The role of inland water bodies in avian influenza (AI) outbreaks has not been investigated. Identifying water bodies that facilitate risk pathways leading to the incursion of the HPAI virus (HPAIV) into poultry farms is essential for implementing specific precautionary measures to prevent viral transmission. Objectives: This matched case-control study (1:4) examined whether inland waters were associated with a higher risk of AI outbreaks in the neighboring poultry farms. Methods: Rivers, irrigation canals, lakes, and ponds were considered inland water bodies. The cases and controls were chosen based on the matching criteria. The nearest possible farms located within a radius of 3 km of the case farms were chosen as the control farms. The poultry farms were selected randomly, and two HPAI epidemics (H5N8 [2014-2016] and H5N6 [2016-2017]) were studied. Conditional logistic regression analysis was applied. Results: Statistical analysis revealed that inland waters near poultry farms were significant risk factors for AI outbreaks. The study speculated that freely wandering wild waterfowl and small animals contaminate areas surrounding poultry farms. Conclusions: Pet birds and animals raised alongside poultry birds on farm premises may wander easily to nearby waters, potentially increasing the risk of AI infection in poultry farms. Mechanical transmission of the AI virus occurs when poultry farm workers or visitors come into contact with infected water bodies or their surroundings. To prevent AI outbreaks in the future, poultry farms should adopt strict precautions to avoid contact with nearby water bodies and their surroundings.