• 한국동물위생학회지
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• 제44권4호
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• pp.291-297
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• 2021

Severe outbreaks of porcine epidemic diarrhoea virus (PEDV) have continued to re-emerge worldwide. Because of the high mortality rate of suckling piglets in PEDV outbreaks, the disease causes significant economic losses in the pig industry. The limited pre-existing immunity against this virus is thought to cause an explosive increase in infection in pig farms. This study aimed to evaluate the clinical symptoms of PEDV after intentional exposure (feedback). During the first few days of the outbreak in a breeding pig farm, 14 sows showed watery diarrhoea, and the disease subsequently spread rapidly throughout the barn. Pigs that were intentionally exposed to PEDV (n=251) showed watery diarrhoea (46.6%), reduced appetite (17.5%), and vomiting (6.0%). However, 75 exposed pigs (29.9%) showed no clinical signs of disease. Four weeks after the feedback challenge, 34 sows gave birth to litters of piglets, which survived with no diarrhoea. Five weeks after the start of the outbreak, PEDV was not detected in any of the examined samples, including environmental swabs. Thus, early diagnosis, prompt establishment of herd immunity, and strict application of biosecurity are good practices to reduce the mortality rates among new-born piglets and control economic losses in pig farms showing PEDV outbreaks.

• The Plant Pathology Journal
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• 제29권2호
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• pp.193-200
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• 2013

Trichoderma asperellum SKT-1 is a microbial pesticide that is very effective against various diseases. Our study was undertaken to evaluate T. asperellum SKT-1 for induction of resistance against yellow strain of Cucumber mosaic virus (CMV-Y) in Arabidopsis plants. Disease severity was rated at 2 weeks post inoculation (WPI). CMV titre in Arabidopsis leaves was determined by indirect enzyme-linked immunosorbent assay (ELISA) at 2 WPI. Our results demonstrated that among all Arabidopsis plants treated with barley grain inoculum (BGI) of SKT-1 NahG and npr1 plants showed no significant reduction in disease severity and CMV titre as compared with control plants. In contrast, disease severity and CMV titre were significantly reduced in all Arabidopsis plants treated with culture filtrate (CF) of SKT-1 as compared with control plants. RT-PCR results showed increased expression levels of SA-inducible genes, but not JA/ET-inducible genes, in leaves of BGI treated plants. Moreover, expression levels of SA- and JA/ET-inducible genes were increased in leaves of CF treated plants. In conclusion, BGI treatment induced systemic resistance against CMV through SA signaling cascade in Arabidopsis plants. While, treatment with CF of SKT-1 mediated the expression of a majority of the various pathogen related genes, which led to the increased defense mechanism against CMV infection.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.2060-2069
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• 2017

Newcastle disease is a serious infectious disease in the poultry industry. The commercial vaccines can only offer limited protection and some of them are expensive and need adjuvants. At present, DNA vaccines are widely used. However, the immune responses induced by DNA vaccines are too slow and low. Here, we constructed the transfer vectors with a different number of C3d as molecular adjuvants (n = 1, 2, 4, or 6), and the vectors were cloned into the optimal eukaryotic expression plasmid (pVAXI-optiF) that expressed the F gene of Newcastle disease virus (NDV), and named pVAXI-F(o)-C3d1, pVAXI -F(o)-C3d2, pVAXI-F(o)-C3d4, and pVAXI-F(o)-C3d6, respectively. Cell transfection test indicated that pVAXI-F(o)-C3d6 showed the highest expression. In vivo immunization showed that the chickens immunized with pVAXI-F(o)-C3d6 intramuscularly induced better immune responses than the chickens immunized with the other plasmids. The protective efficacy of pVAXI-F(o)-C3d6 was 80% after challenge with the highly virulent NDV strain F48E9. The results in this study showed that C3d6 could be used as a molecular adjuvant to quickly induce an effective immune response to control NDV.

• The Plant Pathology Journal
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• 제25권2호
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• pp.151-156
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• 2009

Tomato spotted wilt virus (TSWV) has occurred on fields annually disease occurrence rates were 73.3% in 2005, 53.3% in 2006 and 41.6% in 2007 at Anyang area in Gyeonggi Province. Seasonal occurrence pattern of TSWV showed a dramatic increase from 8.7% in late May to 30.1 % in early June in 2007 at Anyang area, coincided with the high population of a thrip, Frank-liniella occidentalis at that time. The rate of viruliferous thrips with TSWV on lettuce and red pepper was 20.2% and 52.1%, respectively, in greenhouses. Dazomat, soil fumigation pesticide, reduced TSWV disease incidence drastically on table tomato as treatment the chemical into the soil with humidity in early spring in 2006 and 2007. Spraying insecticide periodically after treatment with Dazomat was more effective to control TSWV than spraying if on plants or applying into the soil of the insecticide during growing season. Control efficiency through treatments both of the soil fumigation and of spraying insecticide was significantly high with 85.3% in 2006 and 87.8% in 2007. Removing the potential vector from the soil of TSWV infested area can be an effective strategy for reducing TSWV disease.

• IMMUNE NETWORK
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• 제23권4호
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• pp.33.1-33.13
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• 2023

Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been acknowledged as an effective mean of preventing infection and hospitalization. However, the emergence of highly transmissible SARS-CoV-2 variants of concern (VOCs) has led to substantial increase in infections among children and adolescents. Vaccine-induced immunity and longevity have not been well defined in this population. Therefore, we aimed to analyze humoral and cellular immune responses against ancestral and SARS-CoV-2 variants after two shots of the BNT162b2 vaccine in healthy adolescents. Although vaccination induced a robust increase of spike-specific binding Abs and neutralizing Abs against the ancestral and SARS-CoV-2 variants, the neutralizing activity against the Omicron variant was significantly low. On the contrary, vaccine-induced memory CD4⁺ T cells exhibited substantial responses against both ancestral and Omicron spike proteins. Notably, CD4⁺ T cell responses against both ancestral and Omicron strains were preserved at 3 months after two shots of the BNT162b2 vaccine without waning. Polyfunctionality of vaccine-induced memory T cells was also preserved in response to Omicron spike protein. The present findings characterize the protective immunity of vaccination for adolescents in the era of continuous emergence of variants/subvariants.

• Journal of Preventive Medicine and Public Health
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• 제53권4호
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• pp.228-232
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• 2020

Coronavirus disease 2019 (COVID-19) is inflicting a brutal blow on humankind, and no corner of the world has been exempted from its wrath. This study analyzes the chief control measures and the distinctive features of the responses implemented by Korea and the United States to contain COVID-19 with the goal of extracting lessons that can be applied globally. Even though both nations reported their index cases on the same day, Korea succeeded in flattening the curve, with 10 752 cases as of April 28, 2020, whereas the outbreak skyrocketed in the United States, which had more than 1 million cases at the same time. The prudent and timely execution of control strategies enabled Korea to tame the spread of the virus, whereas the United States paid a major price for its delay, although it is too early to render a conclusive verdict. Information pertaining to the number of people infected with the virus and measures instituted by the government to control the spread of COVID-19 was retrieved from the United States Centers for Disease Control and Prevention and the Korea Centers for Disease Control and Prevention websites and press releases. Drawing lessons from both nations, it is evident that the resolution to the COVID-19 pandemic lies in the prudent usage of available resources, proactive strategic planning, public participation, transparency in information sharing, abiding by the regulations that are put into place, and how well the plan of action is implemented.

• 한국동물위생학회지
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• 제42권2호
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• pp.73-83
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• 2019

Foot-and-Mouth Disease (FMD) is a highly contagious trans-boundary viral disease caused by FMD virus, which causes huge economic losses. FMDV infects cloven hoofed (two-toed) mammals such as cattle, sheep, goats, pigs and various wildlife species. To control the FMDV, it is necessary to understand the life cycle and the pathogenesis of FMDV in host. Especially, the protein-protein interaction between FMDV and host will help to understand the survival cycle of viruses in host cell and establish new therapeutic strategies. However, the computational approach for protein-protein interaction between FMDV and pig hosts have not been applied to studies of the onset mechanism of FMDV. In the present work, we have performed the prediction of the pig's proteins which interact with FMDV based on RNA-Seq data, protein sequence, and structure information. After identifying the virus-host interaction, we looked for meaningful pathways and anticipated changes in the host caused by infection with FMDV. A total of 78 proteins of pig were predicted as interacting with FMDV. The 156 interactions include 94 interactions predicted by sequence-based method and the 62 interactions predicted by structure-based method using domain information. The protein interaction network contained integrin as well as STYK1, VTCN1, IDO1, CDH3, SLA-DQB1, FER, and FGFR2 which were related to the up-regulation of inflammation and the down-regulation of cell adhesion and host defense systems such as macrophage and leukocytes. These results provide clues to the knowledge and mechanism of how FMDV affects the host cell.

• 한국동물위생학회지
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• 제42권2호
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• pp.117-120
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• 2019

Bovine viral diarrhea Virus (BVDV) infections cause respiratory, gastrointestinal, and reproductive problems, such as infertility, abortion, stillbirth, and sickly offspring. Many countries have reduced the economic damage through the application of different control programmes, and some have successfully eradicated BVD. Detection and elimination of cattle persistently infected (PI) with BVDV is important for BVD eradication because PI cattle are a main source of BVD transmission. In this study, the prevalence of Korean native cattle persistently infected (PI) with BVDV was investigated and determined in 49 farms with 3,050 cattle. The all samples were collected by ear notch sampling. Korean native cattle with initial positives on antigen-ELISA (Ag-ELISA) were sampled again after 3~4 weeks and cattle with second positives in both Ag-ELISA and immunohistochemistry (IHC) were identified as PI cattle. Among the 49 farms, 14 (28.6%) farms had at least more than one PI cow and 21 (0.69%) of 3,050 cattle were determined as PI cattle. As a result of this work, it is suggested that national BVD eradication program is required to reduce economic losses by BVDV infection in Korean cattle industries.

• 환경위생공학
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• 제9권2호
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• pp.41-49
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• 1994

Water- borne infectious diseases can be acquired by contact with contaminated water or by ingestion of contaminated water. There are many water- borne infectious agents such as bacteria, virus, and parasite. Among many of water- borne infectious diseases, health authorities of Korean government has particularly intensified to prevent and control typhoid fever(class I ), shigellosis(class I ), cholera(class I ), paratyphoid fever(class I), amebiasis(class II ) and leptospirosis(euivalent to class II ) under the communicable disease control law. Water- borne disease Prevention and control guideline itself has been also well provided by the health authorities. However, in practical public health point of view, there are still many problems remained to be solved out; no prospective investigation project to survey water borne infectious diseases under the national disease prevention and control programmes, incredible statistic data of annual notifiable disease report frequent appearance and varieties of drug resistance water- borne infectious agents, little cooperation and information- exchange system in between the related government authorities( the health authorities, the environment sanitation authorities and the food hygiene authorities) which should be closely collaborated, lack of health consciousness of the people, necessity of evaluation and Hndification on to the outcomes of performed health activities and programmes, neglect activities for water quality investigation, shortage of expertise and human resources in the related field, and poor investment of the government budget to develope and improve public health and sanitation field. In order to prevent and control water- borne infectious diseases effectively, it is emphasized that all the above indicated should be considered and performed to improve under the national health and sanitation development programmes.

• Journal of Preventive Medicine and Public Health
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• 제38권4호
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• pp.386-390
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• 2005

Influenza A viruses periodicall y cause worldwide epidemics, or pandemics, with high rates of illness and death. A pandemic can occur at any time, with the potential to cause serious illness, death and social and economic disruption throughout the world. Historic evidence suggests that pandemics occurred three to four times per century. In the last century there were three influenza pandemics. The circumstances still exist for a new influenza virus with pandemic potential to emerge an d spread. The unpredictability of the timing of the next pandemic is underlined by the occurrence of several large outbreaks of highly pathogenic avian influenza since the early 1980s. In 1999, the World Health Organization published the Influenza pandemic plan. The role of WHO and guidelines for national and regional planning. And in 2005, WHO revised the global influenza preparedness plan for new national measures before and during pandemics. This document outlines briefly the Korean Centers for Disease Control's plan for responding to an influenza pandemic. According to the new pandemic phases of WHO, we set up the 4 national levels of preparedness and made guidelines for preventing and control the epidemics in each phase. And also we described the future plans to antiviral stockpiles and pandemic vaccine development.