• Journal of the Korean Data and Information Science Society
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• 제28권2호
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• pp.297-307
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• 2017

질병 확산 모형은 질병의 확산 과정을 모형화 함으로써 질병이 발생하고 퍼지는 시간 내에서 통제하기 위하여 활용하고자 하는 모형이다. 본 연구에서는 질병 확산 모형의 가장 대표적인 SIR 모형에 기본적인 확장 접근을 하여 접촉군 (exposed)이라는 단계를 추가한 SEIR 모형을 이용하여 모형 구축을 하였다. 이 모형은 감염 대상군 (susceptible)의 사람들이 질병에 노출 된 잠복기를 거쳐 일정 시간이 경과한 후 감염되어 감염군 (infected)으로 이동한 후 다시 회복군 (removed)으로 이동하는 모형이다. 이와 같이 질병에 감염된 후 감염력이 생기는 잠복기가 있는 경우에 연구에 활용될 수 있다. 본 연구에서는 2015년 국내에서 발생한 메르스 코로나바이러스 (Middle East respiratory syndrome coronavirus; MERS CoV)에 의한 호흡기 감염증 자료를 수집하였다. 질병의 확산 과정이 결정적이 아닌 확률적인 흐름을 따른다고 가정하여 포아송 확률과정을 따른다고 보고 확률적 화학반응 모형을 이용하여 모형을 구축하였다. 모형을 구현하기 위해서 SEIR 모형의 세 모수인 질병에 노출된 정도를 나타내는 접촉률 (exposed rate), 질병의 감염 정도를 나타내는 감염률 (transmission rate), 질병의 회복정도를 나타내는 회복률 (recovery rate)를 추정함으로써, SEIR 모형에 적합하고 전염병 확산에 대한 예측을 수행하였다. 또한 접촉군이 정확하게 관찰되지 않을 부분을 보완하기 위하여 접촉군을 생성하는 과정을 전체 모형 구축 과정에 추가하였다.

• Journal of Preventive Medicine and Public Health
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• 제55권1호
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• pp.19-27
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• 2022

This study estimated the direct and indirect socioeconomic costs of 238 diseases and 22 injuries from a social perspective in Korea from 2007 to 2015. The socioeconomic cost of each disease group was calculated based on the Korean Standard Disease Classification System. Direct costs were estimated using health insurance claims data provided by the National Health Insurance Service. The numbers of outpatients and inpatients with the main diagnostic codes for each disease were selected as a proxy indicator for estimating patients' medical use behavior by disease. The economic burden of disease from 2007 to 2015 showed an approximately 20% increase in total costs. From 2007 to 2015, communicable diseases (including infectious, maternal, pediatric, and nutritional diseases) accounted for 8.9-12.2% of the socioeconomic burden, while non-infectious diseases accounted for 65.7-70.7% and injuries accounted for 19.1-22.8%. The top 5 diseases in terms of the socioeconomic burden were self-harm (which took the top spot for 8 years), followed by cirrhosis of the liver, liver cancer, ischemic heart disease, and upper respiratory infections in 2007. Since 2010, the economic burden of conditions such as low back pain, falls, and acute bronchitis has been included in this ranking. This study expanded the scope of calculating the burden of disease at the national level by calculating the burden of disease in Koreans by gender and disease. These findings can be used as indicators of health equality and as useful data for establishing community-centered (or customized) health promotion policies, projects, and national health policy goals.

• 보건교육건강증진학회지
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• 제32권3호
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• pp.1-9
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• 2015

Objectives: The purpose of this article was to assess epidemiological characteristics and recommendations for strengthening national response and preparedness after MERS-CoV outbreak in Korea, 2015. Methods: The author reviewed epidemiological reports and policy recommendations on MERS-CoV outbreak in Korea, 2015. Results: There was no evidence that genetical difference between the MERS viruses in the Republic of Korea and recent viruses in the Middle East. From the index case to last laboratory-confirmed case, there were 186 laboratory-confirmed cases that included 36 deaths(19.4%), all of whom appear epidemiologically linked to the index cases or subsequent secondary, tertiary, and quaternary cases. This outbreak spread to hospitals through nosocomial transmission. At least, three large clusters were investigated. However, there was at least one case of community transmission of MERS-CoV. Several factors had contributed to the MERS outbreak in Korea, 2015 that including epidemiological characteristics, and infrastructure of national healthcare system for preventing and controlling emerging infectious diseases. Conclusions: It is very important that to share experiences and identify underlying causes of this outbreak for prevention and control of emerging infectious disease in the future; including epidemiology, clinical features, and public health response and preparedness.

• International journal of advanced smart convergence
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• 제9권4호
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• pp.132-138
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• 2020

Worldwide, the number of corona virus disease 2019 (COVID-19) confirmed cases is rapidly increasing. Although vaccines and treatments for COVID-19 are being developed, the disease is unlikely to disappear completely. By attaching a smart sensor to the respirator worn by medical staff, Internet of Things (IoT) technology and artificial intelligence (AI) technology can be used to automatically detect the medical staff's infection symptoms. In the case of medical staff showing symptoms of the disease, appropriate medical treatment can be provided to protect the staff from the greater risk. In this study, we design and develop a system that detects cough, a typical symptom of respiratory infectious diseases, by applying IoT technology and artificial technology to respiratory protection. Because the cough sound is distorted within the respirator, it is difficult to guarantee accuracy in the AI model learned from the general cough sound. Therefore, coughing and non-coughing sounds were recorded using a sensor attached to a respirator, and AI models were trained and performance evaluated with this data. Mel-spectrogram conversion method was used to efficiently classify sound data, and the developed cough recognition system had a sensitivity of 95.12% and a specificity of 100%, and an overall accuracy of 97.94%.

• Tuberculosis and Respiratory Diseases
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• 제85권4호
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• pp.313-319
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• 2022

Environmental exposure to air pollution is known to have adverse effects on various organs. Air pollution has greater effects on the pulmonary system as the lungs are directly exposed to contaminants in the air. Here, we review the associations of air pollution with the development, morbidity, and mortality of pulmonary diseases. Short-and long-term exposure to air pollution have been shown to increase mortality risk even at concentrations below the current national guidelines. Ambient air pollution has been shown to be associated with lung cancer. Particularly long-term exposure to particulate matter with a diameter <2.5 ㎛ (PM_2.5) has been reported to be associated with lung cancer even at low concentrations. In addition, exposure to air pollution has been shown to increase the incidence risk of chronic obstructive pulmonary disease (COPD) and has been correlated with exacerbation and mortality of COPD. Air pollution has also been linked to exacerbation, mortality, and development of asthma. Exposure to nitrogen dioxide (NO₂) has been demonstrated to be related to increased mortality in patients with idiopathic pulmonary fibrosis. Additionally, air pollution increases the incidence of infectious diseases, such as pneumonia, bronchitis, and tuberculosis. Furthermore, emerging evidence supports a link between air pollution and coronavirus disease 2019 transmission, susceptibility, severity and mortality. In conclusion, the stringency of air quality guidelines should be increased and further therapeutic trials are required in patients at high risk of adverse health effects of air pollution.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제23권3호
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• pp.251-258
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• 2020

Purpose: Proton-pump inhibitors (PPIs) are frequently used to treat gastroesophageal reflux disease (GERD) in children, but recent evidence suggests a potential association between PPI treatment and some types of infections. The aim of this study was to assess the effectiveness of Lactobacillus rhamnosus GG (LGG) for the prevention of gastrointestinal and respiratory tract infections in children with GERD treated with PPI (omeprazol). Methods: Children younger than 5 years with GERD were assigned by a computer-generated list to receive LGG (10⁹ colony-forming units) or placebo, twice daily, concomitantly with PPI treatment for 4-6 weeks; they were followed up for 12 weeks after therapy. The primary outcome measures were the percentage of children with a minimum of one episode of respiratory tract infection and the percentage of children with a minimum of one episode of gastrointestinal infection during the study. Results: Of 61 randomized children, 59 patients (LGG n=30; placebo n=29, mean age 11.3 months) were analyzed. There was no significant difference found between the LGG and placebo groups, either for the proportion of children with at least one respiratory tract infection (22/30 vs. 25/29, respectively; relative risk [RR] 0.85, 95% confidence interval [CI] 0.66-1.10) or for the proportion of children with at least one gastrointestinal infection (9/30 vs. 9/29, respectively; RR 0.97, 95% CI 0.45-2.09). Conclusion: LGG was not effective in the prevention of infectious complications in children with GERD receiving PPI. Caution is needed in interpreting these results, as the study was terminated early due to slow subject recruitment.

• Allergy, Asthma & Respiratory Disease
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• 제6권6호
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• pp.284-289
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• 2018

Purpose: Vitamin D plays an important role in calcium homeostasis and bone metabolism. It is associated with various diseases such as cardiovascular, immune, allergic and infectious disease. The aim of this study was to investigate the difference in clinical manifestations according to the concentration of vitamin D in mild bronchiolitis. Methods: We performed a retrospective review of medical records of patients with mild bronchiolitis from November 2016 to April 2017 in Daegu Fatima Hospital. Mild bronchiolitis was classified by the modified Tal's score method. Patients were divided into 2 groups according to a 25-hydroxyvitamin D level of 20 ng/mL. We analyzed the clinical characteristics and laboratory data from the 2 groups. Results: Of the 64 patients, 19 were included in the deficiency group and 45 in the normal group. Vitamin D levels were $11.7{\pm}4.9ng/mL$ in the deficiency group and $28.8{\pm}5.0ng/mL$ in the normal group. There were no differences in clinical features between both groups. However, the vitamin D deficiency group had significantly longer hospitalization than the normal group ($6.78{\pm}2.74$ days vs. $5.3{\pm}1.7$ days, P=0.045). In the deficiency group, the incidence of previous respiratory diseases was significantly higher (P=0.001). No significant difference in blood and respiratory virus tests was observed. Conclusion: Low vitamin D levels in mild bronchiolitis were associated with longer hospitalization and prior respiratory disease. Vitamin D may affect the course of mild bronchiolitis.

• 월간양계
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• 제33권7호통권381호
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• pp.100-105
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• 2001

마이코플라즈마 갈리셉티쿰(Mycoplasma gallisepticum, MG)및 마이코플라즈마 시노비에(M. synoviae,MS)에 의한 감염증은 아시아지역 뿐만 아니라 전세계적으로 닭에서 흔히 발생하는 질병이다. MG 감염은 흔히 닭에서 기낭염을 수반하는 만성호흡기병(chronic respiratory disease, CRD)과 칠면조의 전염성부비동염(infectious sinusitis)을 일으킨다. MS는 처음에 육계에서 전염성활막염(infectious synovitis)을 유발하는 병원체로만 알려졌으나, MG에 감염되지 않은 육계의 기낭염 병변부에서 빈번히 분리됨으로 인해 최근에는 원래의 전염성활막염보다 기낭염과 관련하여 많은 관심이 고조되고 있다. 아시아지역의 마이코플라즈마 감염상황을 대변하는 많은 문헌자료가 있으나, 대부분이 자국의 언어로 출판되어 있는 관계로 자료분석에 많은 애로가 있어 주로 해독이 가능한 영문자료를 근거로 하여 각국의 닭에서의 MG 및 MS 감염증의 발생상황과 방제현황에 대하여 언급하고자 한다. 비록 개략적이 나마 이를 토대로 국내 마이코플라즈마 방역상황을 되돌아볼 수 있는 계기가 되었으면 한다.

• Journal of Veterinary Science
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• 제21권3호
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• pp.51.1-51.5
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• 2020

A novel coronavirus emerged in human populations and spread rapidly to cause the global coronavirus disease 2019 pandemic. Although the origin of the associated virus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) remains unclear, genetic evidence suggests that bats are a reservoir host of the virus, and pangolins are a probable intermediate. SARS-CoV-2 has crossed the species barrier to infect humans and other animal species, and infected humans can facilitate reverse-zoonotic transmission to animals. Considering the rapidly changing interconnections among people, animals, and ecosystems, traditional roles of veterinarians should evolve to include transdisciplinary roles.

• Journal of Veterinary Science
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• 제22권1호
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• pp.12.1-12.11
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• 2021

Background: Bats have been considered natural reservoirs for several pathogenic human coronaviruses (CoVs) in the last two decades. Recently, a bat CoV was detected in the Republic of Korea; its entire genome was sequenced and reported to be genetically similar to that of the severe acute respiratory syndrome CoV (SARS-CoV). Objectives: The objective of this study was to compare the genetic sequences of SARS-CoV, SARS-CoV-2, and the two Korean bat CoV strains 16BO133 and B15-21, to estimate the likelihood of an interaction between the Korean bat CoVs and the human angiotensin-converting enzyme 2 (ACE2) receptor. Methods: The phylogenetic analysis was conducted with the maximum-likelihood (ML) method using MEGA 7 software. The Korean bat CoVs receptor binding domain (RBD) of the spike protein was analyzed by comparative homology modeling using the SWISS-MODEL server. The binding energies of the complexes were calculated using PRODIGY and MM/GBGA. Results: Phylogenetic analyses of the entire RNA-dependent RNA polymerase, spike regions, and the complete genome revealed that the Korean CoVs, along with SARS-CoV and SARS-CoV-2, belong to the subgenus Sarbecovirus, within BetaCoVs. However, the two Korean CoVs were distinct from SARS-CoV-2. Specifically, the spike gene of the Korean CoVs, which is involved in host infection, differed from that of SARS-CoV-2, showing only 66.8%-67.0% nucleotide homology and presented deletions within the RBD, particularly within regions critical for cross-species transmission and that mediate interaction with ACE2. Binding free energy calculation revealed that the binding affinity of Korean bat CoV RBD to hACE2 was drastically lower than that of SARS-CoV and SARS-CoV-2. Conclusions: These results suggest that Korean bat CoVs are unlikely to bind to the human ACE2 receptor.