• 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.

• Biomedical Science Letters
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• v.17 no.4
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• pp.297-304
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• 2011

Influenza A virus of the Orthomyxoviridae family is a contagious respiratory pathogen that continues to evolve and burden in the human public health. It is able to spread efficiently from human to human and have the potential to cause pandemics with significant morbidity and mortality. It has been estimated that every year about 500 million people are infected with this virus, causing about approximately 0.25 to 0.5 million people deaths worldwide. Influenza A viruses are classified into different subtypes by antigenicity based on their hemagglutinin (HA) and neuraminidase (NA) proteins. The sudden emergence of influenza A virus subtypes and access for epidemiological analysis of this subtypes demanded a rapid development of specific diagnostic tools. Also, rapid identification of the subtypes can help to determine the antiviral treatment, because the different subtypes have a different antiviral drug resistance patterns. In this study, our aim is to detect influenza A virus subtypes by using real-time nucleic acid sequence based amplification (NASBA) which has high sensitivity and specificity through molecular beacon. Real-time NASBA is a method that able to shorten the time compare to other molecular diagnostic tools and is performed by isothermal condition. We selected major pandemic influenza A virus subtypes, H3N2 and H5N1. Three influenza A virus gene fragments such as HA, NA and matrix protein (M) gene were targeted. M gene is distinguished influenza A virus from other influenza virus. We designed specific primers and molecular beacons for HA, NA and M gene, respectively. In brief, the results showed that the specificity of the real-time NASBA was higher than reverse transcription polymerase chain reaction (RT-PCR). In addition, time to positivity (TTP) of this method was shorter than real-time PCR. This study suggests that the rapid detection of neo-appearance pandemic influenza A virus using real-time NASBA has the potential to determine the subtypes.

• 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.

• 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.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.419-419
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• 2014

Interdigitated nanogap device (IND) is an attractive tool for biomolecular detection due to its huge on-off signal ratio, great tolerance to the variation in biochemical environment, and relatively simple implementation processes. Here, we report on the IND-based detection of Influneza A virus by sandwich immunoassay. The INEs were fabricated by photo lithography followed by the in-house chemical lithographic technique for the narrowing the initial gap distance. The surface of the silicon oxide between the two gold electrodes was chemically modified to immobilize primary antibodies for the immuno-specific interaction with the influenza A virus antigen. After immersing the functionalized-IND into the sample solution containing the influenza A virus, the device was exposed to the secondary antibody conjugated Au nanoparticles (Au NPs). The INDs showed a huge jump in the electric conductance when the sample solution contained the influenza A virus of the concentration as low as 10 ng/mL. We hope that this IND-based sensing can be applied to the development of simple and reliable diagnostic means of influenza viruses.

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.52.2-52.2
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• 2007

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• Journal of Ginseng Research
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• v.36 no.4
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• pp.396-402
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• 2012

Vaccination is the main strategy for preventing influenza infection. However, vaccine efficacy is influenced by several factors, including age and health status. The efficacy of the influenza vaccine is much lower (17% to 53%) in individuals over 65 yr of age compared with young adults (70% to 90%). Therefore, increasing vaccine efficacy remains a challenge for the influenza vaccine field. In this study, we investigated the impact of supplementing vaccination with the dietary intake of Korean red ginseng (RG) extract and RG saponin. Mice were immunized two times intranasally with inactivated influenza A (H1N1) virus. Mice received RG extract or RG saponin orally for 14 d prior to the primary immunization. After the primary immunization, mice continued to receive RG extract or RG saponin until the secondary immunization. Mice vaccinated in combination with dietary intake of RG extract and RG saponin showed elevated serum anti-influenza A virus IgG titers and improved survival rates in lethal influenza A virus infection: 56% and 63% of mice receiving RG extract or RG saponin survived, respectively, while 38% of mice that only received the vaccine survived. Moreover, mice receiving RG extract supplementation recovered their body weight more quickly than those not receiving RG extract supplementation. We propose that the dietary intake of RG extract and RG saponin enhances the vaccine-induced immune response and aids in providing protection against influenza virus infection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.128-133
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• 2000

This study was designed to verify the efficacy of garlic extracts for protecting the infecton of influenza and Japanese B encephalitis virus. Influenza virus (AO/PR8 strain) and Japanese B encephalitis virus (JaGAr O1 strain) were used to attack mouse through nasal route and each vaccines were injected subcutaneously. 0.002 and 0.2 mL/day of garlic extracts were orally administered to mice. The blood and serum samples were taken from the mice to measure LD50, Defense Index (DI), virus-neutralizing antibody for comparing virus influence inhibiting activities. Defense indices of the male and female mice were not significantly different at every experiment. Vaccination effectively inhibited the influence of influenza virus and 0.002 mL/day garlic extract (0.55$\pm$0.05) resulted in significantly higher DI than the control (0$\pm$0.05) (p<0.05). Although 0.002 mL/day garlic extract (0.55$\pm$0.05) resulted in significantly lower DI than the vaccination (1.10$\pm$0.05), 0.2 mL/day garlic extract (2.05$\pm$0.05) resulted in 10 times higher DI than the vaccination (1.10$\pm$0.05). Garlic extract did not affect DI in Japanese B encephalitis virus influence of the vaccinated mouse, but significantly reduced DI of the non-vaccinated mouse (p<0.05). Garlic extracts did not affect the production of the neutralizing antibody against influenza by vaccination. However, neutralizing antibody production of Japanese B encephalitis was accelerated by vaccination. Consequently, the current study proved the efficacy of garlic on inhibition of influenza virus. Finally, it is very hard to show the higher preventing effect on flu through ingestion of garlic as a food than vaccination.

• Journal of Medicine and Life Science
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• v.17 no.3
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• pp.98-102
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• 2020

Influenza is a common disease that causes epidemics yearly due to the influenza virus. If patients with influenza present with rare symptoms, the diagnosis may be delayed and the condition is difficult to treat. A 5-year-old boy presented to the emergency room with fever and cramps. Brain computed tomography showed low attenuation in the thalamus and brain stem, which was suggestive of encephalopathy caused by influenza virus. Another 5-year-old girl visited the emergency room with mild fever and painful calf edema. She was diagnosed with myositis caused by influenza and treated accordingly.

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.273-283
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• 1996

In order to search for anti-influenza virus type A agents from Korean traditional prescriptions (herb complexes), we selected 63 traditional prescriptions, based on a review of the Korean traditional medicine books. Both methanol extracts and boiling-water extracts were tested, by means of the Haemagglutination Inhibition Test (HIT). Three of the 63 methanol extracts: CM-22, CM-26, CM-48 (see explanation of nomenclature below), showed efficacy against influenza virus type ACM-22 showed anti-influenza virus type A activity at the range of $313{\mu}g/ml$ to $9.75{\mu}g/ml$, CM-26 showed antiviral activity at the range of $156{\mu}l/ml$ to $4.87{\mu}g/ml$, CM-48 showed anti-influenza virus type A activity at the range of $625{\mu}g/ml$ to $19.5{\mu}g/ml$, respectively. Three of the water extracts: CW-14, CW-34, CW-61 were active. CW-14 showed anti-influenza virus type A activity at the range of l0mg/ml to $78{\mu}g/ml$, CW-34 showed antiviral activity at the range of 10mg/ml to $625{\mu}g/ml$ and CW-61 showed anti-influenza virus type A activity at the range of l0mg/ml to $313{\mu}g/ml$, respectively. In order to determine cytotoxicity of each extracts, chicken red blood cells were incubated with the various concentration of extracts of Korean traditional prescriptions. CW-14, CW-34 and CW-61 did not show cytotoxic effect against red blood cells whereas CM-22, CM-26 and CM-48 showed cytotoxic effect against red blood cells at the range of l0mg/ml to $625{\mu}g/ml$, 10mg/ml to $313{\mu}g/ml$ and 10mg/ml to $313{\mu}g/ml$, respectively. These results indicated that Korean traditional pres criptions may be inhibit either attachment of virus to cell surface receptor or penetration of the virus into cell during the initial stage of infection.