• Tuberculosis and Respiratory Diseases
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• 제69권1호
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• pp.24-30
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• 2010

Background: A novel 2009 influenza A (H1N1) virus emerged and disseminated to all over the world. There are few reports on the clinical characteristics of patients with complications. We describe the clinical features of pneumonia in adult patients hospitalized, who have novel influenza infection. Methods: There were 43 adult patients enrolled into the study with pneumonia of 528 hospitalized patients confirmed influenza A (H1N1) virus infection by real-time reverse transcriptase polymerase chain reaction testing, between 24 August 2009 and 31 January 2010. The clinical data of patients with pneumonia were collected retrospectively. Results: There were 22 of 43 (51.2%) influenza patients with pneumonia that had higher risk factors for complications. Compared to 28 patients with influenza A (H1N1) viral pneumonia and 15 patients, who had isolated bacteria from cultures, those with mixed viral and bacterial pneumonia were significantly more likely to have unilobar consolidations on chest radiographs (53.3 vs. 10.7%, p<0.01) and higher scores of pneumonia severity index (PSI; 90 [66~100] vs. 53 [28~90], p=0.04). Six patients required mechanical ventilation support in an Intensive Care Unit and were more likely to have dyspnea (83.3 vs. 29.3%, p=0.02) and low levels of $PaO_2$ (48.3 [37.0~70.5] vs 64.0 [60.0~74.5] mm Hg, p=0.02) and high levels of pneumonia severity index (PSI) score (108.0 [74.5~142.8] vs. 56.0 [40.5~91.0], p=0.03). Conclusion: The majority of pneumonia patients infected with novel influenza improved. Chest radiographic findings of unilobar consolidations suggest that mixed pneumonia is more likely. Initial dyspnea, hypoxemia, and high levels of PSI score are associated with undergoing mechanical ventilation support.

• 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.

• Animal Bioscience
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• 제35권3호
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• pp.367-376
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• 2022

Objective: The highly pathogenic avian influenza virus (HPAIV) is a threat to the poultry industry as well as the economy and remains a potential source of pandemic infection in humans. Antiviral genes are considered a potential factor for HPAIV resistance. Therefore, in this study, we investigated gene expression related to cytokine-cytokine receptor interactions by comparing resistant and susceptible Ri chicken lines for avian influenza virus infection. Methods: Ri chickens of resistant (Mx/A; BF2/B21) and susceptible (Mx/G; BF2/B13) lines were selected by genotyping the Mx dynamin like GTPase (Mx) and major histocompatibility complex class I antigen BF2 genes. These chickens were then infected with influenza A virus subtype H5N1, and their lung tissues were collected for RNA sequencing. Results: In total, 972 differentially expressed genes (DEGs) were observed between resistant and susceptible Ri chickens, according to the gene ontology and Kyoto encyclopedia of genes and genomes pathways. In particular, DEGs associated with cytokine-cytokine receptor interactions were most abundant. The expression levels of cytokines (interleukin-1β [IL-1β], IL-6, IL-8, and IL-18), chemokines (C-C Motif chemokine ligand 4 [CCL4] and CCL17), interferons (IFN-γ), and IFN-stimulated genes (Mx1, CCL19, 2'-5'-oligoadenylate synthase-like, and protein kinase R) were higher in H5N1-resistant chickens than in H5N1-susceptible chickens. Conclusion: Resistant chickens show stronger immune responses and antiviral activity (cytokines, chemokines, and IFN-stimulated genes) than those of susceptible chickens against HPAIV infection.

• 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.

• 미생물학회지
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• 제41권1호
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• pp.53-59
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• 2005

인플루엔자바이러스는 거의 매년 겨울철에 유행을 일으키는 급성 호흡기 질환의 주요한 원인 바이러스중의 하나로 막대한 사회 경제적 손실을 가져온다. 본 실험은 2003-2004절기 동안 $38^{\circ}C$이상의 갑작스러운 발열과 더불어 기침 또는 인후통을 보이는 401명의 인플루엔자의사환자(ILI : Influenza-like illness) 검체로부터 124주의 인플루엔자바이러스를 분리하여 형 및 아형 분석과 그에 따른 유행양상을 분석하였다. 인플루엔자 의사환자 연령별 분포를 살펴보면 20-49세의 성인층의 환자수가 $23\%$로 가장 많았으며, 바이러스 분리율은 7-19세의 학령기에서 $50\%$로 가장 높았다. 분리된 인플루엔자바이러스 124주 중 A/H3N2 type는 83주, Type B는 41주였다. 지역별 인플루엔자 의사환자 발생율은 노원구, 서초구, 강남구의 발생율이 타 지역에 비해 비교적 높았으며 바이러스 분리율은 용산구 $66.7\%$, 강남구 $50.0\%$, 노원구 $39.9\%$, 강북구 $36.8\%$ 서초구 $27.8\%$, 동작구 $21.2\%$ 순이었다. 인플루엔자 의사환자의 예방접종현황조사결과 접종을 받았음에도 불구하고 인플루엔자 의사환자로 보고된 경우가 $40\%$였으며, 접종율은 20-49세 성인층이 가장 높았다. 이와 같은 인플루엔자 실험실 표본감시체계 결과의 분석을 통하여 새로운바이러스형 출현을 감시하며, 현행 예방백신의 효과 및 유행양상을 예측하여 국가 인플루엔자 관리대책을 수립하는데 활용하고자 한다.

• 한국지리정보학회지
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• 제18권3호
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• pp.89-101
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• 2015

본 연구는 질병역학의 관점에서 2014년 발생한 HPAI(H5N8)의 시간적 분포와 공간적 분포 그리고 시 공간을 동시에 고려한 분포를 지리정보시스템과 연계하여 분석함으로써 2014년 발생한 HPAI의 전파 및 확산 특징을 알아보고자 한다. 분석 결과 2014년 HPAI는 시간적으로는 모두 3 번의 파동을 형성하였으며, 공간적으로는 경기도 충청북도 충청남도가 인접하는 지역, 전라북도의 곰소만 일대, 전라남도의 영암과 나주 등 영산강과 인접한 지역에서 높은 밀도를 보였다. 시 공간적으로도 공간 밀도가 높은 충청북도 음성지역, 전라북도 부안 고창지역, 나주지역에서 군집이 형성되었다. 다만, 충청북도 음성 진천, 충청남도 천안, 경기도 안성 이천 지역과 전라남도 영암 지역에서는 공간적인 밀도는 높음에도 불구하고 시간적인 범위가 넓음으로써 시 공간 군집이 형성되지 못하였다. 이는 이들 지역의 방역에 문제가 있음을 의미한다. 반면에 곰소만과 인접하고 있는 전라북도 부안 고창 장수 지역은 시 공간 군집이 형성됨으로써, 상대적으로 효과적인 방역이 수행되었다고 볼 수 있다.