• Pediatric Infection and Vaccine
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• v.18 no.2
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• pp.173-181
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• 2011

Purpose : 2009 Pandemic influenza A (H1N1) virus was identified in March 2009 and subsequently caused worldwide outbreaks. We described the clinical and epidemiological characteristics of H1N1 influenza infection. Methods : We used retrospective medical chart reviews to collect data on the visiting patients from a single institute. H1N1 infection was confirmed in specimens with the use of a RT-PCR (real time reverse transcriptase polymerase chain reaction assay). Result : 6,836 patients had H1N1 RT-PCR test, and 2,781 were confirmed with H1N1 virus infection. 158 patients (5.7%) had hospital treatment and inpatients were significantly younger (5.4${\pm}$3.3 years) than outpatients (7.5${\pm}$3.9 years) among H1N1 virus confirmed patients. Oxygen, steroid, immunoglobulin, ventilator treatment was provided in a substantial proportion among pneumonia patients accompanying wheezy respiration. In addition more intensive care was needed in patients accompanying segmental, lobar, interstitial, mixed pneumonia and lung effusion (27.2%) than patients with bronchopneumonia (7.3%) among H1N1 virus infection confirmed patients. Seventy-one infants had oseltamivir treatment out of 83 infants under 1 year, and no significant side effects and complications were identified. Conclusion : In 2009 pandemic influenza A (H1N1), hospital treatment was needed in younger patients. Early intensive care was needed in pneumonia patients accompanying wheezy respiration, and patients accompanying segmental, lobar, interstitial, mixed pneumonia and lung effusion.

• Clinical and Experimental Pediatrics
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• v.55 no.12
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• pp.474-480
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• 2012

Purpose: For evaluating the immunogenicity of an influenza vaccine, the microneutralization (MN) test has a higher sensitivity and specificity as compared to the hemagglutination inhibition (HI) test. However, the MN test is more time consuming and is difficult to standardize. We performed the MN test to determine its usefulness as an alternative or complementary test to the HI test for evaluating the immunogenicity of influenza vaccines. Methods: We compared the MN test with the HI test using 50 paired samples taken from a previous clinical study (2008-2009) in Korean children under 18 years of age. Results: The linear correlation coefficients of the 2 tests for H3N2, H1N1, and influenza B were 0.69, 0.70, and 0.66, respectively. We identified a high index of coincidence between the 2 tests. For an influenza vaccine, the postvaccination seroprotection rates and seroconversion rates determined by the MN test were 78.0% and 96.0%, 90% and 42.0%, and 42.0% and 48.0% for H3N2, H1N1, and influenza B, respectively. Geometric mean titer fold increases of H3N2, H1N1, and influenza B were 2.89, 5.04, and 4.29, respectively, and were 2.5-fold higher. We obtained good results in the evaluation of the immunogenicity of the 2008-2009 seasonal influenza vaccines. Conclusion: We found that the MN test was as effective as the HI test. Therefore, we suggest that the MN test can be used as an alternative or complementary test to the HI test for evaluating the immunogenicity of influenza vaccines.

• Korean Journal of Clinical Laboratory Science
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• v.41 no.4
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• pp.145-152
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• 2009

Novel influenza A virus, subtype H1N1 of swine-lineage, has been transmitted rapidly to many regions of the world. Rapid detection of the virus is essential to instigate appropriate patient care and public health management and for disease surveillance. The aim of this study is to determine the prevalence of novel influenza A (H1N1) virus in Korea using reverse-transcription real time polymerase chain reaction (rRT-PCR). Novel H1N1 virus was detected in a total of 8,948 nasopharyngeal samples from patients with influenza-like illness throughout Korea from August to September 2009. RNA was extracted from $300{\mu}l$of sample using an RNA extraction kit (Zymo Research, CA, USA). In the present study, Genekam kit (Genekam, Duisburg, Germany) was used to detect novel H1N1 virus. Novel H1N1 virus was found in 1,130 samples from a total of 8,948 samples (12.6%). The highest frequency was found in 10- to 19-year-olds (M: 29.3% vs. F: 16.4%), followed by 20- to 29-year-olds (M: 17.9% vs. F: 15.4%), 40- to 49-year-olds (M: 6.5% vs. F: 8.1%), 50- to 59-year-olds (M: 6.0% vs. F: 5.5%), and 30- to 39-year-olds (M: 4.6% vs. F: 3.8%). The mean positive rate was higher in men than in women (M: 14.7% vs. F: 7.4%). Novel H1N1 virus showed the lowest prevalence in patients over 60 years old. The positive rate increased daily and showed a significant high peak in mid-September 2009. In 19 provinces of Korea, Cheonan (41.1%), Busan (37.3%), Gangneung (33.3%), Jinju (32.1%), Ulsan (24.6%), Deajeon (23.7%) areas showed high frequencies and other provinces were found less than 10% of novel H1N1 virus. Since reverse-transcription real time PCR assay is rapid, accurate, and convenient, it may assist public health laboratories in detecting novel H1N1 virus. Moreover, these data could be useful for the management of patients with influenza-like illness.

• Korean Journal of Microbiology
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• v.43 no.3
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• pp.173-178
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• 2007

The occurrence of acute respiratory infections caused by the influenza virus are particularly high during the winter season in Busan, Korea. In 2004 and 2005, a study of the rate of occurrences of the influenza virus was conducted. The results reveal that in 2004, of the 1,869 people with an acute respiratory infection that 154 (8.2%) people were infected by the influenza virus. In 2005, of the 1,579 people infected with an acute respiratory infection that 19 people (1.2%) were infected with the influenza virus. The study shows a decrease in the numbers of an influenza virus infection from 2004 to 2005. Data was collected by inspecting throat swabs and nasal discharge from those with an acute respiratory infection. Further inspection of the throat swab and nasal discharge from the infected individuals during 2004 and 2005 study show the occurrence of the different types of influenza virus in the population: 6 cases (3.5%) of influenza type A/H1N1, 129 cases (74.5%) of A/H3N2, and 38 cases (22.0%) of type B. The study conducted in 2004 and 2005 reveal that children between the ages of two and five were more likely to be infected than any other age group. In the study, about 62.2% of the infected individuals were between two and five years old. The detection rates between males and females are similar. However, it is notable that females are slightly more likely to develop an acute respiratory infection caused by the influence virus compared to their male counterparts.

• Journal of the Korea Convergence Society
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• v.12 no.4
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• pp.201-206
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• 2021

Damage to the highly pathogenic avian influenza virus(H5N1) continues to increase, but there is a lack of antiviral research. In this study, we analyze antiviral properties on H5N1 by coating Cu/TiO2 photocatalyst on polyethylene films. The specimen was manufactured a photocatalyst master batch and coated both sides of the 3-layer polyethylene fabric at 280℃ from the extrusion coating machine. The results showed a 99.9% decrease in the Staphylococcus aureus and Escherichia coli. In particular, H5N1 type highly pathogenic avian influenza viruses, which is capable of human infection, has been found to decrease 99.9% within five minutes of contact with Cu/TiO2 films. Antibacterial effects of films coated with photocatalyst are known, but this study also confirmed the antiviral effects.

• Genomics & Informatics
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• v.20 no.2
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• pp.21.1-21.14
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• 2022

The influenza A viruses have high mutation rates and cause a serious health problem worldwide. Therefore, this study focused on genome characterization of the viruses isolated from Thai patients based on the next-generation sequencing technology. The nasal swabs were collected from patients with influenza-like illness in Thailand during 2017-2018. Then, the influenza A viruses were detected by reverse transcription-quantitative polymerase chain reaction and isolated by MDCK cells. The viral genomes were amplified and sequenced by Illumina MiSeq platform. Whole genome sequences were used for characterization, phylogenetic construction, mutation analysis and nucleotide diversity of the viruses. The result revealed that 90 samples were positive for the viruses including 44 of A/H1N1 and 46 of A/H3N2. Among these, 43 samples were successfully isolated and then the viral genomes of 25 samples were completely amplified. Finally, 17 whole genomes of the viruses (A/H1N1, n=12 and A/H3N2, n=5) were successfully sequenced with an average of 232,578 mapped reads and 1,720 genome coverage per sample. Phylogenetic analysis demonstrated that the A/H1N1 viruses were distinguishable from the recommended vaccine strains. However, the A/H3N2 viruses from this study were closely related to the recommended vaccine strains. The nonsynonymous mutations were found in all genes of both viruses, especially in hemagglutinin (HA) and neuraminidase (NA) genes. The nucleotide diversity analysis revealed negative selection in the PB1, PA, HA, and NA genes of the A/H1N1 viruses. High-throughput data in this study allow for genetic characterization of circulating influenza viruses which would be crucial for preparation against pandemic and epidemic outbreaks in the future.

• Tuberculosis and Respiratory Diseases
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• v.70 no.5
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• pp.397-404
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• 2011

Background: To evaluate chest CT findings of pandemic influenza A/H1N1 pneumonia without co-infection. Methods: Among 56 patients diagnosed with pandemic influenza A/H1N1 pneumonia, chest CT was obtained in 22 between October 2009 and Februrary 2010. Since two patients were co-infected with bacteria, the other twenty were evaluated. Predominant parenchymal patterns were categorized into consolidation, ground glass opacity (GGO), and mixed patterns. Distribution of parenchymal abnormalities was assessed. Results: Median age was 46.5 years. The CURB-65 score, which is the scoring system for severity of community acquired pneumonia, had a median of 1. Median duration of symptoms was 3 days. All had abnormal chest x-ray findings. The median number of days after the hospital visit that Chest CT was performed was 1. The reasons for chest CT performance were radiographic findings unusual for pneumonia (n=13) and unexplained dyspnea (n=7). GGO was the most predominant pattern on CT (n=13, 65.0%). Parenchymal abnormalities were observed in both lungs in 13 cases and were more extensive in the lower lung zone than the upper. Central and peripheral distributions were identified in ten and nine cases, respectively. One showed diffuse distribution. Peribronchial wall thickening was found in 16 cases. Centrilobular branching nodules (n=7), interlobular septal thickening (n=4), atelectasis (n=1), pleural effusion (n=5), enlarged hilar and mediastinal lymph nodes (n=6 and n=7) were also noted. Conclusion: Patchy and bilateral GGO along bronchi with predominant involvement of lower lungs are the most common chest CT findings of pandemic influenza A/H1N1 pneumonia.

• Journal of the Korean Professional Engineers Association
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• v.42 no.6
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• pp.42-46
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• 2009

Every year influenza contributes to the death of 72 people in the South korea, 20,000 in the U.S. and perhaps millions worldwide. The swine fever so-called the noble flu A H1N1, a strain of the flu virus, which jumped species and burst into the human population in March and April of this year. The outbreak of 2009 novel H1N1 was the fourth in 100 years. Fortunately, it led to today's comparatively tame swine flu than the vicious 1918, which was original H1N1 pandemic flu virus, killed at least 40 million worldwide in an ongoing pandemic era. Although the 2009 H1N1 which is still in full swing, this global flu epidemic is already teaching scientists valuable lessons about pandemics. Evidence accumulated these days indicates that the 2009 H1N1 was not entirely new to all human immune systems. This article introduces only an outline for our better understanding the basic mechanisms of influenza and the vaccination about longstanding fears of that worst-case scenario engendered pandemic that are paying off today.

• Proceedings of the Korea Contents Association Conference
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• 2014.11a
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• pp.57-58
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• 2014

인플루엔자 A 바이러스의 아형인 H5N1은 고병원성으로 조류 독감을 일으킨다. H5N1 바이러스는 원래 조류끼리만 감염되는 독감이고, 사람에게는 전염되지 않는다고 알려져 있었으나, 2003년에 베트남과 중국을 시작으로 현재까지 168명의 사망자가 기록되고 있다. 그러나 현재 시판되고 있는 진단키트(Rapid diagnostic kits)들은 H5N1 에 특이적인 것이 아니라 influenza A virus 모두를 진단한다. 따라서 influenza 감염여부는 확인 할 수 있지만, 이것이 H5N1 인지는 확인 할 수가 없다. H5N1은 전염성이 강하기 때문에 빠르게 진단하여 감염조류를 살 처분 하여야 더 많은 경제적 손실을 줄일 수 있다. 따라서 H5N1 에만 특이적인 epitope를 네트워크 기반으로 예측하여 진단제에 응용할 수 있도록 하고자 한다. 각 서열 정보는 Openflu (http://openflu. vital-it.ch/browse.php)에서 얻었다. H5N1은 H1N1에서 유래되었기 때문에 두 subtype의 차이점을 알아보고자 TCOFFEE에서 multiple sequence alignment를 수행한 결과 N-terminal 부분이 상이하였다. 상이한 H5N1의 N-terminal 부분이 H5N1 virus에 감염된 모든 host에서 존재하는지 알아보기 위해 host가 사람인 경우와 조류인 경우를 TCOFFEE에서 alignment 하였다. 그 결과 H5N1의 N-terminal 부분은 사람과 조류에서 보존적이었다. 따라서 H5N1의 N-terminal이 다른 subtype과 유사하지 않고 H5에만 특이적이기 때문에 진단키트 제작을 위한 epitope로 사용할 수 있을 것으로 기대된다.

• Korean Journal of Pharmacognosy
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• v.31 no.1
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• pp.82-86
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• 2000

To evaluate anti-influenza virus activity of 113 specimens of Korean traditional medicine both water and methanol extracts were examined using haemagglutination inhibition test. The water extract from Citrus junos was found to inhibit influenza virus A/Taiwan/l/86(H1N1). The survival rates of virus were determined by in situ cellular enzyme-linked immunosorbent assay. The water extract of Citrus junos was fractionated by chromatographic separating using Amberlite XAD-4, 40% MeOH and 60% MeOH layer had antiviral activity. The half inhibition concentration $(IC_{50})$ of 40% MeOH layer on survival of influenza virus was $MIC>361.5{\mu}g/ml$ and $IC_{50}$ value of fr. 40-4 fractionated from 40% MeOH layer was $677.19{\mu}g/ml$. These results suggested that the fractions of Citus junos have potent anti-influenza A virus activity.