• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1470-1474
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• 2009

This paper describes the development a of direct multiplex reverse transcription-nested polymerase chain reaction (PCR) method, devised for simultaneous detection and typing of influenza viruses. This method combines the direct reverse transcription reaction without RNA purification with the enhancement of sensitivity and specificity of nested PCR. The method successfully detected three major human influenza viruses: influenza virus A subtype 1 (H1N1) and subtype 3 (H3N2), and influenza B virus (B). The minimum number of virus particles (pfu/ml) necessary for detection in spiked saliva samples was 200 (H1N1), 140 (H3N2), and 4.5 (B). The method's sensitivity and simplicity will be convenient for use in clinical laboratories for the detection and subtyping of influenza and possibly other RNA viruses.

• Korean Journal of Veterinary Research
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• v.47 no.3
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• pp.273-279
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• 2007

Swine influenza is an acute, infectious respiratory disease caused by type A influenza viruses in pigs. In the previous studies, serological surveys have indicated the presence of H3N2 swine influenza virus (SIV) since 1995 in Korea. And the percentage of the antibody-positive rate was 39.12% in the survey determining the prevalence of H1N1 SIV antibodies in 2002. The purpose of this study was therefore to investigate the sero-prevalence of SIV regard to the age of the pig and the season between June 2004 and May 2005. In this study, a total of 932 sera were used. These sera were randomly selected from blood samples, which were submitted to Department of Veterinary Pathology, Kangwon National University and Department of Veterinary Virology, Seoul National University from June 2004 to May 2005. These sera have been tested by ELISA test kit (IDEXX Lab, USA) for the SIV H3N2, H1N1 respectively. SAS version 9.1 was used for the statistical analysis based on the age of the pig and the season. The overall sero-prevalence of the antibody against H3N2 SIV was 20.82% (194/932). The overall sero-prevalence of the antibody against H1N1 SIV was 37.23% (347/932). The overall dual sero-prevalence of the antibody against H3N2 and H1N1 SIV was 10.62% (99/932). H3N2 has significant difference in statistically regarding the age of the pig and the season (p<0.0001). H1N1 has significant difference in statistically regarding the age of the pig (p<0.0001) but has not significant difference in statistically regarding the season (p=0.5882).

• Journal of Preventive Medicine and Public Health
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• v.52 no.5
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• pp.308-315
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• 2019

Objectives: Estimating influenza-associated mortality is important since seasonal influenza affects persons of all ages, causing severe illness or death. This study aimed to estimate influenza-associated mortality, considering both periodic changes and age-specific mortality by influenza subtypes. Methods: Using the Microdata Integrated Service from Statistics Korea, we collected weekly mortality data including cause of death. Laboratory surveillance data of respiratory viruses from 2009 to 2016 were obtained from the Korea Centers for Disease Control and Prevention. After adjusting for the annual age-specific population size, we used a negative binomial regression model by age group and influenza subtype. Results: Overall, 1 859 890 deaths were observed and the average rate of influenza virus positivity was 14.7% (standard deviation [SD], 5.8), with the following subtype distribution: A(H1N1), 5.0% (SD, 5.8); A(H3N2), 4.4% (SD, 3.4); and B, 5.3% (SD, 3.7). As a result, among individuals under 65 years old, 6774 (0.51%) all-cause deaths, 2521 (3.05%) respiratory or circulatory deaths, and 1048 (18.23%) influenza or pneumonia deaths were estimated. Among those 65 years of age or older, 30 414 (2.27%) all-cause deaths, 16 411 (3.42%) respiratory or circulatory deaths, and 4906 (6.87%) influenza or pneumonia deaths were estimated. Influenza A(H3N2) virus was the major contributor to influenza-associated all-cause and respiratory or circulatory deaths in both age groups. However, influenza A(H1N1) virus-associated influenza or pneumonia deaths were more common in those under 65 years old. Conclusions: Influenza-associated mortality was substantial during this period, especially in the elderly. By subtype, influenza A(H3N2) virus made the largest contribution to influenza-associated mortality.

• Korean Journal of Veterinary Research
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• v.52 no.4
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• pp.223-230
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• 2012

The worldwide distribution and continuing genetic mutation of avian influenza virus (AIV) has been posed a great threat to human and animal health. A comparison of 3 isolates of AIV H9N2, A/chicken/Korea/KBNP-0028/00 (H9N2) (KBNP-0028), A/chicken/Korea/SNU8011/08 (H9N2) (SNU 8011) and an inactivated oil vaccine strain A/chicken/Korea/01310/01 (H9N2) (01310), was performed. The former 2 AIVs were isolated from field cases before and after the application of an inactivated H9N2 vaccine in 2007, respectively. The antigenic relationship, viral shedding, tissue tropism and genetic analysis were examined. The comparison of virus shedding from the cloaca and the oropharynx revealed that both isolates were more frequently isolated from the upper respiratory tract (90~100%) 1 day post inoculation (DPI) compared with isolation 5 DPI from gastrointestinal tracts (10~60%). Moreover, the isolate KBNP-0028 were recovered from all organs including bone marrow, brain and kidneys, indicating higher ability for broad tissue dissemination than that of SNU 8011. KBNP-0028 replicated earlier than other strains and with a higher titer than SNU 8011. In full-length nucleotide sequences of the NA gene and a partial sequence of the HA gene of SNU 8011, we found that there might be significant changes in tissue tropism, virus replication and genetic mutation in AIV H9N2 isolates.

• Korean Journal of Microbiology
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• v.37 no.4
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• pp.284-288
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• 2001

Respiratory viruses are one of the most infectious agent in human. Six different respiratory tract viruses were detected from Busan while working on the preventive surveillance in 1997-2000. The isolation rate from suspected specimens were 8.4%. Influenza virus A, B type, parainfluenza virus, adenovirus, mumps virus, and measles virus were examined from throat swabs, serum, and secretions of patients. Influenza A/Sydney/05/97(H3N2)-like, A/Johanesburg/33/94(H3N2)-like, A/Beijing/262/95(H1N1)-like and Influenza B/Beijing/262/95-like, B/Harbin/07/94-like, B/Guangdong/08/93-like were found. Adenovirus serotype 1, 2, 3 and 5 were detected, antibody of mumps both IgM and IgG were shown and outbreaks of measles were confirmed. Different antigenic types of influenza virus were detected every year, one outbreak of parainfluenza in 1999, mumps outbreak in 1999 and 2000, and incidence of measles in 2000 were noticeable. Monthly outbreaks were November through following March with influenza virus, January through June with adenovirus, February through May and December with mumps, April through August and November, December with measles, respectively. The size of isolated viruses were 130 nm with influenza virus B type, non-enveloped, icosahedron with 70 nm with adenovirus, 170 nm with mumps virus and 180 nm with parainfluenza virus in diameter, respectively.

• Biomolecules & Therapeutics
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• v.26 no.3
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• pp.290-297
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• 2018

We aimed to understand the molecular changes in host cells that accompany infection by the seasonal influenza A H1N1 virus because the initial response rapidly changes owing to the fact that the virus has a robust initial propagation phase. Human epithelial alveolar A549 cells were infected and total RNA was extracted at 30 min, 1 h, 2 h, 4 h, 8 h, 24 h, and 48 h post infection (h.p.i.). The differentially expressed host genes were clustered into two distinct sets of genes as the infection progressed over time. The patterns of expression were significantly different at the early stages of infection. One of the responses showed roles similar to those associated with the enrichment gene sets to known 'gp120 pathway in HIV.' This gene set contains genes known to play roles in preventing the progress of apoptosis, which infected cells undergo as a response to viral infection. The other gene set showed enrichment of 'Drug Metabolism Enzymes (DMEs).' The identification of two distinct gene sets indicates that the virus regulates the cell's mechanisms to create a favorable environment for its stable replication and protection of gene metabolites within 8 h.

• Clinical and Experimental Pediatrics
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• v.48 no.3
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• pp.260-265
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• 2005

Purpose : During epidemics, influenza induces a high mortality and morbidity, and when influenza is prevalent, it is revealed by increased pneumonia, hospitalization due to influenza-like illness, and mortality in community. We aimed at the isolation of influenza virus and prevalence period in Busan from 2000 to 2002. Methods : For 3 years from 2000 to 2002, we analyzed the patterns of influenza virus, the occurrence distribution of influenza by age and sex and the prevalence period after cultivating the examined materials from throat smears and snivel, collected from patients in St. Benedict Hospital Pediatrics Department, from 10 monitoring hospitals, and from 16 public health centers. Results : For three years, a total of 209 strains of influenza virus were isolated. In 2000, there were A/sydney/05/97(H3N2)-like, A/Beijing/262/95(H1N1)-like and B/Harbin/07/94-like. In 2001, there were A/Panama/2007/99(H3N2)-like and A/Newcaledonia/20/99(H1N1)-like. In 2002, there were A/Panama/2007/99(H3N2)-like, A/Newcaledonia/20/99(H1N1)-like, B/Beijing/243/97, B/Honkong/22/2001 and B/Sichuam/379/99. The occurrence distribution by sexes were 14 males and 25 females in 2000, 23 males and 33 females in 2001, 57 males and 57 females in 2002. As for the occurrence distribution by ages, 0-10 years made up 48.4 percent in 2000, 11-20 years 33.93 percent in 2001, and below 10 years was 64.91 percent in 2002. As for the occurrence distribution by month, the rate was once high in January and somewhat high in April and by June, when there happened to be various viruses, though there was a low rate in 2000. On the other hand, the virus was concentrated in February and March in 2001. And in 2002, it happened high twice, in March and November. Conclusion : Influenza virus revealed frequent antigenic changes and infect children, especially those below 10 years of age from late fall to early spring. So we should consider appropriate prevention in children.

• Journal of Veterinary Science
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• v.21 no.4
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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.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.340-344
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• 2007

Avian influenza viruses cause a considerable threat to humans and animals. In this study, we investigated whether alkaline disinfectant solution can inactivate H5N1, H3N2, H6N1, and H9N2 subtypes of avian influenza virus. When H5N1, H3N2, H6N1, and H9N2 avian influenza viruses were treated with alkaline solution diluted with PBS (pH 7.2) prior to infection into MDCK cells, alkaline disinfectant solution (at dilutions up to $10^{-2}$) completely inactivated all avian influenza subtypes tested. To confirm the inactivation of avian influenza viruses by alkaline disinfectant solution, we used an immunofluorescence assay with influenza A anti-nucleoprotein antibody and FITC-labeled secondary antibody to stain MDCK cells infected with avian H9N2 influenza viruses. No staining was observed in MDCK rells infected with H9N2 viruses that were pre-treated with a $10^{-2}$ dilution of alkaline disinfectant solution, while strong staining was observed in MDCK cells infected with H9N2 viruses without pre-treatment. Our results indicate that alkaline solution could help to control avian influenza viruses including the highly pathogenic H5N1 subtype.

• Korean Journal of Clinical Pharmacy
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• v.21 no.4
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• pp.353-363
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• 2011

The World Health Organization (WHO) declared the outbreak of H1N1 pandemic in 2009. South Korea also had outbreaks of H1N1 virus and used oseltamivir in large volume with increased reports of adverse drug reaction(ADR). The present study was aimed to investigate the ADR frequency, the factors related to ADR, and characteristics of oseltamivir's ADR. Participants for the study were patients randomly drawn from those who were prescribed oseltamivir for treatment from CHA Bundang Medical Center during October 1 and October 30. The information examined as factors related to ADR were collected by a subsequent cross-sectional telephone survey. The factors are the following; a) age; b) gender; c) patient medical history; d) diagnosis of H1N1 virus; e) adherence; f) whether taking other medication with oseltamivir or not; and g) the number of combined medications. We also asked ADR after taking oseltamivir. Total subjects were 86 patients. The average age is $22.6{\pm}18.48$ years old. The gender was 45.3% women and 54.7% men. Half (50%) of all respondents showed one or more ADR, 67.4% were positively diagnosed for H1N1 virus, and 54.7% were completed the full course of oseltamivir (i.e. twice daily x 5days). The most frequently reported ADR symptoms were: dizziness (15.1%), nausea (11.6%), lethargy (10.4%), diarrhea (10.4%), abdominal pain (8.1%), headache and vomiting (6.9%). ADR classifications by categories are gastro intestinal (44.2%), neuropsychiatric events (22.1%), systemic symptom (20.9%), skin events (5.8%), eye events (4.7%), and other cases (2.3%). The onset of ADR 'after taking 1~3 doses' was 69.7%. No increase in neuropsychiatric events was detected in children and adolescents. No factors examined for the study do have significant influence on the presence of ADR. This study showed that ADR of oseltamivir have occurred in half of the patients. The use of oseltamivir is essential for treatment and prophylaxis of influenza A(H1N1). But mass treatment should be properly monitored for ADR.