• Tuberculosis and Respiratory Diseases
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• v.70 no.4
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• pp.285-292
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• 2011

After an outbreak of H1N1 influenza A virus infection in Mexico in late March 2009, the World Health Organization raised its pandemic alert level to phase 6, and to the highest level in June 2009. The pandemic H1N1/A influenza was caused by an H1N1 influenza A virus that represents a quadruple reassortment of two swine strains, one human strain, and one avian strain of influenza. After the first case report of H1N1/A infection in early May 2009, South Korea was overwhelmed by this new kind of influenza H1N1/A pandemic, which resulted in a total of 700,000 formally reported cases and 252 deaths. In this article, clinical characteristics of victims of H1N1/A influenza infection, especially those who developed pneumonia and those who were cared for in the intensive care unit, are described. In addition, guidelines for the treatment of H1N1/A influenza virus infection victims in the ICU, which was suggested by the Korean Society of Critical Care Medicine, are introduced.

• Journal of Preventive Medicine and Public Health
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• v.40 no.2
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• pp.185-190
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• 2007

Objectives : Since the first human infection from avian influenza was reported in Hong Kong in 1997, many Asian countries have confirmed outbreaks of highly pathogenic H5N1 avian influenza viruses. In addition to Asian countries, the EU authorities also held an urgent meeting in February 2006 at which it was agreed that Europe could also become the next target for H5N1 avian influenza in the near future. In this paper, we provide the general and applicable information on the avian influenza in the bioinformatics field to assist future studies in preventive medicine. Methods : We introduced some up-to-date analytical tools in bioinformatics research, and discussed the current trends of avian influenza outbreaks. Among the bioinformatics methods, we focused our interests on two topics: pattern analysis using the secondary database of avian influenza, and structural analysis using the molecular dynamics simulations in vaccine design. Results : Use of the public genome databases available in the bioinformatics field enabled intensive analysis of the genetic patterns. Moreover, molecular dynamic simulations have also undergone remarkable development on the basis of the high performance supercomputing infrastructure these days. Conclusions : The bioinformatics techniques we introduced in this study may be useful in preventive medicine, especially in vaccine and drug discovery.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1683-1690
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• 2018

Accurate and rapid diagnosis of influenza infection is essential to enable early antiviral treatment and reduce the mortality associated with seasonal and epidemic infections. Immunochromatography is one of the most common methods used for the diagnosis of seasonal human influenza; however, it is less effective in diagnosing pandemic influenza virus. Currently, rapid diagnostic kits for pandemic influenza virus rely on the detection of nucleoprotein (NP) or hemagglutinin (HA). NP detection shows higher specificity and is more sensitive than HA detection. In this study, we time-dependently screened expression conditions, and herein report optimal conditions for the expression of recombinant nucleoprotein (rNP), which was 48 h after infection. In addition, we report the use of the expressed rNP in a rapid influenza diagnostic test (SGT i-flex Influenza A&B Test). We constructed expression vectors that synthesized rNP (antigen) of influenza A and B in insect cells (Sf9 cells), employed the purified rNP to the immunoassay test kit, and clearly distinguished NPs of influenza A and influenza B using this rapid influenza diagnostic kit. This approach may improve the development of rapid test kits for influenza using NP.

• Genomics & Informatics
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• v.20 no.4
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• pp.46.1-46.7
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• 2022

Influenza A virus (IAV) is the most widespread pathogen causing human respiratory infections. Although polymerase chain reaction (PCR)-based methods are currently the most commonly used tools for IAV detection, PCR is not ideal for point-of-care testing. In this study, we aimed to develop a more rapid and sensitive method than PCR-based tools to detect IAV using loop-mediated isothermal amplification (LAMP) technology. We designed reverse-transcriptional (RT)-LAMP primers targeting the hemagglutinin gene. RNAs from reference H1N1 and H3N2 showed specific RT-LAMP signals with the designed primers. We optimized the reaction conditions and developed universal reaction conditions for both LAMP assays. Under these conditions, the detection limit was 50 copies for both RT-LAMP assays. There was no non-specific signal to 19 non-IAV respiratory viruses, such as influenza B virus, coronaviruses, and respiratory syncytial viruses. Regarding the reaction time, a positive signal was detected within 25 min after starting the reaction. In conclusion, our RT-LAMP assay has high sensitivity and specificity for the detection of the H1 and H3 subtypes, making it suitable for point-of-care IAV testing.

• Journal of Life Science
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• v.30 no.9
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• pp.749-762
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• 2020

Influenza A viruses are circulating in a variety of hosts, including humans, pigs, and poultry. Swine influenza virus is a zoonotic pathogen that can be readily transmitted to humans. The influenza viruses of the 2009 H1N1 pandemic were derived from swine influenza viruses, and it has been suggested that the 1957 H2N2 pandemic and the 1968 H3N2 pandemic both originated in pigs. Pigs are regarded as a mixing vessel in the creation of novel influenza viruses since they are readily infected with human and avian influenza viruses. We isolated three novel H1N2 influenza viruses from pigs showing respiratory symptoms on a Korean farm in 2019. These viruses were reassortants, containing PA and NP genes from those of the 2009 H1N1 influenza virus in addition to PB2, PB1, HA, NA, M, and NS genes from those of triple-reassortant swine H3N2 and classical swine H1N2 influenza viruses circulating in Korean pigs. Mice infected with the isolated H1N2 influenza virus lost up to 17% body weight and exhibited interstitial pneumonia involving infiltration of many inflammatory cells. Results suggest that close surveillance to detect emerging influenza viruses in pigs is necessary for the health of both pigs and humans.

• The Journal of Korean Society for School & Community Health Education
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• v.19 no.3
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• pp.15-27
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• 2018

Objectives: This study aims to investigate the estimated proportion for influenza vaccination and to identify factors associated with influenza vaccination in Korean adults aged 50 and older with asthma. Methods: Data from 2010-2015 Community Health Survey(n=23,662) was used. A chi-square test was performed to investigate the estimated proportion for influenza vaccination, and a multiple logistic regression analysis was used to identify the factors associated with self-reported influenza vaccination. Results: In men, 42.3-49.5% of asthma patients 50-64 years of age, and 78.5-90.2% of elderly (over 65 years of age) asthma patients received influenza vaccination. In women, 49.7-61.9% of asthma patients 50-64 years of age, and 82.7-89.7% of elderly asthma patients received influenza vaccination(p<0.0001). Low education level, non-smoking, non-drinking, hypertension, diabetes and use of public center were related to high influenza vaccination in 50-64 years old men with asthma. Low education level, non-smoking, bad health status, hypertension, diabetes and use of public center were related to high influenza vaccination in 50-64 years old women with asthma. Non-smoking and use of public center were related to high influenza vaccination in over 65 years old men with asthma. White-collar jobs, smoking, absence of hypertension and use of public center were related to low influenza vaccination in over 65 years old women with asthma. Conclusions: Influenza vaccination remains relatively low in asthma patients 50-64 years of age. It is necessary to recommend vaccination to asthma patients, provide them with information, and devise other strategies to improve vaccination.

• Research in Community and Public Health Nursing
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• v.32 no.2
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• pp.175-185
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• 2021

Purpose: Influenza immunization among health personnel is of particular importance given their elevated risk of influenza infection, role in transmission and influence on patients' immunization status. The purpose of this study is to identify factors associated with the influenza vaccination intention among health personnel based on the theory of planned behavior. Methods: The research was a cross-sectional, descriptive design using questionnaires. The participants were 131 health personnel in five general hospitals in two cities in South Korea. The data were analyzed using descriptive statistics, t-test, ANOVA and multiple regression with the SPSS 26.0 program. Results: There were statistically significant differences in influenza vaccination intention according to the high-risk group in the family, occupation, length of employment, and influenza vaccination status within a year. The influenza vaccination intention of these health personnel showed significant positive correlations with attitude, subjective norms, and perceived behavioral control towards influenza vaccination. Multiple regression analysis for influenza vaccination intention revealed that the significant predictors were attitude, subjective norms, influenza vaccination within a year and physician in occupation. These factors explained 41.4% of the variance. Conclusion: The results suggest a need to strengthen attitude and subjective norms. The findings also suggest that their characteristics through influenza vaccination status within a year and occupation should be considered for tailored interventions related to the intention. Furthermore, it is necessary to develop programs strengthening attitude and subjective norms to enhance influenza vaccination intention among health personnel.

• Tuberculosis and Respiratory Diseases
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• v.84 no.3
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• pp.226-236
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• 2021

Background: Although the Quidel Sofia rapid influenza fluorescent immunoassay (FIA) is widely used to identify influenza A and B, the diagnostic accuracy of this test remains unclear. Thus, the objective of this study was to determine the diagnostic performance of this test compared to reverse transcriptase-polymerase chain reaction. Methods: A systematic literature search was performed using MEDLINE, EMBASE, and the Cochrane Central Register. Pooled sensitivity, specificity, diagnostic odds ratio (DOR), and a hierarchical summary receiver-operating characteristic curve (HSROC) of this test for identifying influenza A and B were determined using meta-analysis. A sensitivity subgroup analysis was performed to identify potential sources of heterogeneity within selected studies. Results: We identified 17 studies involving 8,334 patients. Pooled sensitivity, specificity, and DOR of the Quidel Sofia rapid influenza FIA for identifying influenza A were 0.78 (95% confidence interval [CI], 0.71-0.83), 0.99 (95% CI, 0.98-0.99), and 251.26 (95% CI, 139.39-452.89), respectively. Pooled sensitivity, specificity, and DOR of this test for identifying influenza B were 0.72 (95% CI, 0.60-0.82), 0.98 (95% CI, 0.96-0.99), and 140.20 (95% CI, 55.92-351.54), respectively. The area under the HSROC for this test for identifying influenza A was similar to that for identifying influenza B. Age was considered a probable source of heterogeneity. Conclusion: Pooled sensitivities of the Quidel Sofia rapid influenza FIA for identifying influenza A and B did not quite meet the target level (≥80%). Thus, caution is needed when interpreting data of this study due to substantial betweenstudy heterogeneity.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.893-901
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• 2018

Influenza viruses that cause recurrent seasonal epidemics to humans can be controlled with vaccine and antiviral therapy. However, the medical treatments often exhibit limited efficacy in the elderly or immunosuppressed individuals. In these cases, daily uptake of probiotics may be an option to bring in health benefits against influenza. Here, we demonstrate the effects of probiotics Lactobacillus plantarum (Lp) and Leuconostoc mesenteroides (Lm) against seasonal and avian influenza viruses. As assessed by the plaque size reduction of human H1N1 and avian influenza H7N9 viruses, including green fluorescent protein-tagged H1N1 strain in cells, the selected Lp and Lm strains restrained viral replication in mouse lungs with statistical significance. Against lethal viral challenge, the Lp and Lm strains exhibited their beneficial effects by increasing the mean days and rates of survival of the infected mice. These results suggest that, despite rather narrow ranges of protective efficacy, the dietary supplement of Lactobacillus and Leuconostoc probiotics may promote health benefits against influenza.

• Journal of Preventive Medicine and Public Health
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• v.38 no.4
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• pp.373-378
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• 2005

Influenza virus has a unique characteristics of annual epidemics of acute respiratory disease with attack rate of 10%-30% of the population. It is also the classical emerging infectious disease causing global pandemics when new antigenic shift occur. This antigenic shift is the key to its ability to evoke periodic pandemics, and it has caused at least 3 pandemics in 20th century. I reviewed these 3 pandemics in their natural courses and the epidemiology of the recent emerging influenza A viruses, especially the H5 and H7 subtypes. I descr ibed the epidemics of these vi ruses in human population and why we should be prepared to these viruses.