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Original Articles
Identification of Coronavirus Isolated from a Patient in Korea with COVID-19
Jeong-Min Kim, Yoon-Seok Chung, Hye Jun Jo, Nam-Joo Lee, Mi Seon Kim, Sang Hee Woo, Sehee Park, Jee Woong Kim, Heui Man Kim, Myung-Guk Han
Osong Public Health Res Perspect. 2020;11(1):3-7.   Published online February 28, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.1.02
  • 40,209 View
  • 1,180 Download
  • 261 Citations
AbstractAbstract PDF
Objectives

Following reports of patients with unexplained pneumonia at the end of December 2019 in Wuhan, China, the causative agent was identified as coronavirus (SARS-CoV-2), and the 2019 novel coronavirus disease was named COVID-19 by the World Health Organization. Putative patients with COVID-19 have been identified in South Korea, and attempts have been made to isolate the pathogen from these patients.

Methods

Upper and lower respiratory tract secretion samples from putative patients with COVID-19 were inoculated onto cells to isolate the virus. Full genome sequencing and electron microscopy were used to identify the virus.

Results

The virus replicated in Vero cells and cytopathic effects were observed. Full genome sequencing showed that the virus genome exhibited sequence homology of more than 99.9% with SARS-CoV-2 which was isolated from patients from other countries, for instance China. Sequence homology of SARS-CoV-2 with SARS-CoV, and MERS-CoV was 77.5% and 50%, respectively. Coronavirus-specific morphology was observed by electron microscopy in virus-infected Vero cells.

Conclusion

SARS-CoV-2 was isolated from putative patients with unexplained pneumonia and intermittent coughing and fever. The isolated virus was named BetaCoV/Korea/KCDC03/2020.

Middle East Respiratory Syndrome Coronavirus Outbreak in the Republic of Korea, 2015
Osong Public Health Res Perspect. 2015;6(4):269-278.   Published online August 31, 2015
DOI: https://doi.org/10.1016/j.phrp.2015.08.006
Correction in: Osong Public Health Res Perspect 2016;7(2):138
  • 2,515 View
  • 55 Download
  • 166 Citations
AbstractAbstract PDF
Objectives
The outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in the Republic of Korea started from the index case who developed fever after returning from the Middle East. He infected 26 cases in Hospital C, and consecutive nosocomial transmission proceeded throughout the nation. We provide an epidemiologic description of the outbreak, as of July 2015.
Methods
Epidemiological research was performed by direct interview of the confirmed patients and reviewing medical records. We also analyzed the incubation period, serial interval, the characteristics of superspreaders, and factors associated with mortality. Full genome sequence was obtained from sputum specimens of the index patient.
Results
A total of 186 confirmed patients with MERS-CoV infection across 16 hospitals were identified in the Republic of Korea. Some 44.1% of the cases were patients exposed in hospitals, 32.8% were caregivers, and 13.4% were healthcare personnel. The most common presenting symptom was fever and chills. The estimated incubation period was 6.83 days and the serial interval was 12.5 days. A total of 83.2% of the transmission events were epidemiologically linked to five superspreaders, all of whom had pneumonia at presentation and contacted hundreds of people. Older age [odds ratio (OR) = 4.86, 95% confidence interval (CI) 1.90–12.45] and underlying respiratory disease (OR = 4.90, 95% CI 1.64–14.65) were significantly associated with mortality. Phylogenetic analysis showed that the MERS-CoV of the index case clustered closest with a recent virus from Riyadh, Saudi Arabia.
Conclusion
A single imported MERS-CoV infection case imposed a huge threat to public health and safety. This highlights the importance of robust preparedness and optimal infection prevention control. The lessons learned from the current outbreak will contribute to more up-to-date guidelines and global health security.
Cross-Country Comparison of Case Fatality Rates of COVID-19/SARS-COV-2
Morteza Abdullatif Khafaie, Fakher Rahim
Osong Public Health Res Perspect. 2020;11(2):74-80.   Published online April 30, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.2.03
  • 16,024 View
  • 648 Download
  • 116 Citations
AbstractAbstract PDFSupplementary Material
Objectives

Case fatality rates (CFR) and recovery rates are important readouts during epidemics and pandemics. In this article, an international analysis was performed on the ongoing coronavirus disease 2019 (COVID-19) pandemic.

Methods

Data were retrieved from accurate databases according to the user’s guide of data sources for patient registries, CFR and recovery rates were calculated for each country. A comparison of CFR between countries with total cases ≥ 1,000 was observed for 12th and 23rd March.

Results

Italy’s CFR was the highest of all countries studied for both time points (12th March, 6.22% versus 23rd March, 9.26%). The data showed that even though Italy was the only European country reported on 12rd March, Spain and France had the highest CFR of 6.16 and 4.21%, respectively, on 23rd March, which was strikingly higher than the overall CFR of 3.61%.

Conclusion

Obtaining detailed and accurate medical history from COVID-19 patients, and analyzing CFR alongside the recovery rate, may enable the identification of the highest risk areas so that efficient medical care may be provided. This may lead to the development of point-of-care tools to help clinicians in stratifying patients based on possible requirements in the level of care, to increase the probabilities of survival from COVID-19 disease.

Brief Report
Korea Community Health Survey Data Profiles
Yang Wha Kang, Yun Sil Ko, Yoo Jin Kim, Kyoung Mi Sung, Hyo Jin Kim, Hyung Yun Choi, Changhyun Sung, Eunkyeong Jeong
Osong Public Health Res Perspect. 2015;6(3):211-217.   Published online June 30, 2015
DOI: https://doi.org/10.1016/j.phrp.2015.05.003
  • 1,780 View
  • 21 Download
  • 113 Citations
AbstractAbstract PDF
In 2008, Korea Centers for Disease Control and Prevention initiated the first nationwide survey, Korea Community Health Survey (KCHS), to provide data that could be used to plan, implement, monitor, and evaluate community health promotion and disease prevention programs. This community-based cross-sectional survey has been conducted by 253 community health centers, 35 community universities, and 1500 interviewers. The KCHS standardized questionnaire was developed jointly by the Korea Centers for Disease Control and Prevention staff, a working group of health indicators standardization subcommittee, and 16 metropolitan cities and provinces with 253 regional sites. The questionnaire covers a variety of topics related to health behaviors and prevention, which is used to assess the prevalence of personal health practices and behaviors related to the leading causes of disease, including smoking, alcohol use, drinking and driving, high blood pressure control, physical activity, weight control, quality of life (European Quality of Life-5 Dimensions, European Quality of Life-Visual Analogue Scale, Korean Instrumental Activities of Daily Living ), medical service, accident, injury, etc. The KCHS was administered by trained interviewers, and the quality control of the KCHS was improved by the introduction of a computer-assisted personal interview in 2010. The KCHS data allow a direct comparison of the differences of health issues among provinces. Furthermore, the provinces can use these data for their own cost-effective health interventions to improve health promotion and disease prevention. For users and researchers throughout the world, microdata (in the form of SAS files) and analytic guidelines can be downloaded from the KCHS website (http://KCHS.cdc.go.kr/) in Korean.
Short Communication
Contact Transmission of COVID-19 in South Korea: Novel Investigation Techniques for Tracing Contacts
Osong Public Health Res Perspect. 2020;11(1):60-63.   Published online February 28, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.1.09
  • 33,671 View
  • 1,005 Download
  • 103 Citations
AbstractAbstract PDF

In the epidemiological investigation of an infectious disease, investigating, classifying, tracking, and managing contacts by identifying the patient’s route are important for preventing further transmission of the disease. However, omissions and errors in previous activities can occur when the investigation is performed through only a proxy interview with the patient. To overcome these limitations, methods that can objectively verify the patient’s claims (medical facility records, Global Positioning System, card transactions, and closed-circuit television) were used for the recent ongoing coronavirus disease 2019 contact investigations in South Korea.

Original Articles
Early Epidemiological and Clinical Characteristics of 28 Cases of Coronavirus Disease in South Korea
Osong Public Health Res Perspect. 2020;11(1):8-14.   Published online February 28, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.1.03
  • 19,525 View
  • 732 Download
  • 79 Citations
AbstractAbstract PDF
Objectives

The first confirmed case of coronavirus disease 2019 (COVID-19) in South Korea was reported in January 2020, with 28 confirmed cases reported as of February 14th, 2020. The epidemiological and clinical characteristics of all 28 cases were analyzed in response to this disease.

Methods

The epidemiological characteristics and early clinical features of the 28 patients from Korea with confirmed COVID-19 were analyzed using COVID-19 reporting and surveillance data and the epidemiological investigation reports prepared by the rapid response team.

Results

There were 16 patients that entered Korea from foreign countries: Wuhan, China (11 patients), Zhuhai, China, (1 patient), Singapore (2 patients), Japan (1 patient), and Thailand (1 patient). The early symptoms were fever, sore throat, cough or sputum production, chills, and muscle ache. Three patients were asymptomatic, however, 18 developed pneumonia. Of the 28 cases, 16 were index cases imported from abroad, with 10 cases of secondary infection originating in Korea, and the route of transmission still under investigation for 2 patients. The 10 patients with secondary infection were infected from contact with family members or acquaintances of primary patients, and the suspected sites of transmission were mostly at home.

Conclusion

COVID-19 in Korea was spread by 16 infected individuals traveling from other countries, leading to second-generation cases. The initial symptoms were mostly minor, but the disease was infectious at this stage, resulting from close contact, particularly at home. Establishing an early detection strategy for COVID-19 is crucial for managing the transmission of the disease.

Detection and Isolation of SARS-CoV-2 in Serum, Urine, and Stool Specimens of COVID-19 Patients from the Republic of Korea
Jeong-Min Kim, Heui Man Kim, Eun Jung Lee, Hye Jun Jo, Youngsil Yoon, Nam-Joo Lee, Junseock Son, Ye-Ji Lee, Mi Seon Kim, Yong-Pyo Lee, Su-Jin Chae, Kye Ryeong Park, Seung-Rye Cho, Sehee Park, Su Jin Kim, Eunbyeol Wang, SangHee Woo, Aram Lim, Su-Jin Park, JunHyeong Jang, Yoon-Seok Chung, Bum Sik Chin, Jin-Soo Lee, Duko Lim, Myung-Guk Han, Cheon Kwon Yoo
Osong Public Health Res Perspect. 2020;11(3):112-117.   Published online May 8, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.3.02
  • 10,078 View
  • 508 Download
  • 77 Citations
AbstractAbstract PDF
Objectives

Coronavirus Disease-19 (COVID-19) is a respiratory infection characterized by the main symptoms of pneumonia and fever. It is caused by the novel coronavirus severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), which is known to spread via respiratory droplets. We aimed to determine the rate and likelihood of SARS-CoV-2 transmission from COVID-19 patients through non-respiratory routes.

Methods

Serum, urine, and stool samples were collected from 74 hospitalized patients diagnosed with COVID-19 based on the detection of SARS-CoV-2 in respiratory samples. The SARS-CoV-2 RNA genome was extracted from each specimen and real-time reverse transcription polymerase chain reaction performed. CaCo-2 cells were inoculated with the specimens containing the SARS-COV-2 genome, and subcultured for virus isolation. After culturing, viral replication in the cell supernatant was assessed.

Results

Of the samples collected from 74 COVID-19 patients, SARS-CoV-2 was detected in 15 serum, urine, or stool samples. The virus detection rate in the serum, urine, and stool samples were 2.8% (9/323), 0.8% (2/247), and 10.1% (13/129), and the mean viral load was 1,210 ± 1,861, 79 ± 30, and 3,176 ± 7,208 copy/µL, respectively. However, the SARS-CoV-2 was not isolated by the culture method from the samples that tested positive for the SARS-CoV-2 gene.

Conclusion

While the virus remained detectable in the respiratory samples of COVID-19 patients for several days after hospitalization, its detection in the serum, urine, and stool samples was intermittent. Since the virus could not be isolated from the SARS-COV-2-positive samples, the risk of viral transmission via stool and urine is expected to be low.

Short Communication
Coronavirus Disease-19: The First 7,755 Cases in the Republic of Korea
Osong Public Health Res Perspect. 2020;11(2):85-90.   Published online April 30, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.2.05
Correction in: Osong Public Health Res Perspect 2020;11(3):146
  • 17,547 View
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  • 75 Citations
AbstractAbstract PDF

We report the first 7,755 patients with confirmed COVID-19 in Korea as of March 12th, 2020. A total of 66 deaths have been recorded, giving a case fatality proportion of 0.9%. Older people, and those with comorbidities were at a higher risk of a fatal outcome. The highest number of cases of COVID-19 were in Daegu, followed by Gyeongbuk. This summary may help to understand the disease dynamics in the early phase of the COVID-19 outbreaks, and may therefore, guide future public health measures.

Original Article
Assessment of Antioxidant Potential, Total Phenolics and Flavonoids of Different Solvent Fractions of Monotheca Buxifolia Fruit
Shumaila Jan, Muhammad Rashid Khan, Umbreen Rashid, Jasia Bokhari
Osong Public Health Res Perspect. 2013;4(5):246-254.   Published online October 31, 2013
DOI: https://doi.org/10.1016/j.phrp.2013.09.003
  • 2,092 View
  • 15 Download
  • 68 Citations
AbstractAbstract PDF
Objectives
This study was conducted to investigate the antioxidant potential of methanol extract and its derived fractions (hexane, ethyl acetate, butanol, and aqueous) of fruits of Monotheca buxifolia (Falc.) Dc., a locally used fruit in Pakistan.
Methods
Dried powder of the fruit of M. buxifolia was extracted with methanol and the resultant was fractionated with solvents having escalating polarity; n-hexane, chloroform, ethyl acetate, n-butanol and the residual soluble aqueous fraction. Total phenolic and total flavonoid contents were estimated for the methanol and various fractions. These fractions were also subjected to various in vitro assays to estimate the scavenging activity for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide, hydroxyl, hydrogen peroxide and reductive ability for ferric ions and phosphomolybdate assay.
Results
The n-butanol, aqueous and methanol fractions possessed high amount of phenolics and flavonoids compared with other fractions, and subsequently showed a pronounced scavenging activity on DPPH, ABTS, superoxide, hydroxyl and hydrogen peroxide radicals and had a potent reductive ability on ferric ion and phosphomolybdate assay. There was a found significant correlation between total phenolic and flavonoid contents and EC50 of DPPH, superoxide, hydrogen peroxide radical and phosphomolybdate assays, whereas a nonsignificant correlation was found with the hydroxyl radical and ABTS radical assay.
Conclusion
M. buxifolia fruit can be used as natural antioxidant source to prevent damage associated with free radicals.
Review Article
COVID-19 Outbreak in Malaysia
Asita Elengoe
Osong Public Health Res Perspect. 2020;11(3):93-100.   Published online June 1, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.3.08
  • 65,535 View
  • 3,669 Download
  • 58 Citations
AbstractAbstract PDF

In 2020 a significant threat to public health emerged. The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic outbreak emerged in December 2019 from Wuhan City, Hubei Province, China and spread to the rest of the world. This disease was named COVID-19 by World Health Organization. To date (17th April 2020) a total of 2,230,439 cases of COVID-19; 150,810 cases of deaths and 564,210 recovered cases have been reported worldwide. In this review the SARS-CoV-2 morphology, pathogenic mechanism, similarities and differences between SARS-CoV and Middle East Respiratory Syndrome and severe acute respiratory syndrome, transmission mode, diagnosis, treatment, and preventive measures were investigated. The outbreak of COVID-19 from a Malaysian perspective was explored and mental health care during the COVID-19 outbreak was explored. To date, there is no vaccine or no specific treatment for COVID-19. Therefore, preventive measures are very important to prevent and control the rapid spread of the SARS-CoV-2 virus. Preparedness should be a priority for future pandemic outbreaks.

Original Articles
The Characteristics of Middle Eastern Respiratory Syndrome Coronavirus Transmission Dynamics in South Korea
Yunhwan Kim, Sunmi Lee, Chaeshin Chu, Seoyun Choe, Saeme Hong, Youngseo Shin
Osong Public Health Res Perspect. 2016;7(1):49-55.   Published online February 28, 2016
DOI: https://doi.org/10.1016/j.phrp.2016.01.001
  • 2,369 View
  • 24 Download
  • 55 Citations
AbstractAbstract PDF
Objectives
The outbreak of Middle Eastern respiratory syndrome coronavirus (MERS-CoV) was one of the major events in South Korea in 2015. In particular, this study pays attention to formulating a mathematical model for MERS transmission dynamics and estimating transmission rates.
Methods
Incidence data of MERS-CoV from the government authority was analyzed for the first aim and a mathematical model was built and analyzed for the second aim of the study. A mathematical model for MERS-CoV transmission dynamics is used to estimate the transmission rates in two periods due to the implementation of intensive interventions.
Results
Using the estimates of the transmission rates, the basic reproduction number was estimated in two periods. Due to the superspreader, the basic reproduction number was very large in the first period; however, the basic reproduction number of the second period has reduced significantly after intensive interventions.
Conclusion
It turned out to be the intensive isolation and quarantine interventions that were the most critical factors that prevented the spread of the MERS outbreak. The results are expected to be useful to devise more efficient intervention strategies in the future.
Genome-Wide Identification and Characterization of Point Mutations in the SARS-CoV-2 Genome
Jun-Sub Kim, Jun-Hyeong Jang, Jeong-Min Kim, Yoon-Seok Chung, Cheon-Kwon Yoo, Myung-Guk Han
Osong Public Health Res Perspect. 2020;11(3):101-111.   Published online May 14, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.3.05
  • 11,115 View
  • 488 Download
  • 49 Citations
AbstractAbstract PDF
Objectives

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, in December 2019 and has been rapidly spreading worldwide. Although the causal relationship among mutations and the features of SARS-CoV-2 such as rapid transmission, pathogenicity, and tropism, remains unclear, our results of genomic mutations in SARS-CoV-2 may help to interpret the interaction between genomic characterization in SARS-CoV-2 and infectivity with the host.

Methods

A total of 4,254 genomic sequences of SARS-CoV-2 were collected from the Global Initiative on Sharing all Influenza Data (GISAID). Multiple sequence alignment for phylogenetic analysis and comparative genomic approach for mutation analysis were conducted using Molecular Evolutionary Genetics Analysis (MEGA), and an in-house program based on Perl language, respectively.

Results

Phylogenetic analysis of SARS-CoV-2 strains indicated that there were 3 major clades including S, V, and G, and 2 subclades (G.1 and G.2). There were 767 types of synonymous and 1,352 types of non-synonymous mutation. ORF1a, ORF1b, S, and N genes were detected at high frequency, whereas ORF7b and E genes exhibited low frequency. In the receptor-binding domain (RBD) of the S gene, 11 non-synonymous mutations were observed in the region adjacent to the angiotensin converting enzyme 2 (ACE2) binding site.

Conclusion

It has been reported that the rapid infectivity and transmission of SARS-CoV-2 associated with host receptor affinity are derived from several mutations in its genes. Without these genetic mutations to enhance evolutionary adaptation, species recognition, host receptor affinity, and pathogenicity, it would not survive. It is expected that our results could provide an important clue in understanding the genomic characteristics of SARS-CoV-2.

Review Article
Traditional and Modern Cell Culture in Virus Diagnosis
Ali Hematian, Nourkhoda Sadeghifard, Reza Mohebi, Morovat Taherikalani, Abbas Nasrolahi, Mansour Amraei, Sobhan Ghafourian
Osong Public Health Res Perspect. 2016;7(2):77-82.   Published online April 30, 2016
DOI: https://doi.org/10.1016/j.phrp.2015.11.011
Correction in: Osong Public Health Res Perspect 2020;11(4):266
  • 2,746 View
  • 40 Download
  • 46 Citations
AbstractAbstract PDF
Cell cultures are developed from tissue samples and then disaggregated by mechanical, chemical, and enzymatic methods to extract cells suitable for isolation of viruses. With the recent advances in technology, cell culture is considered a gold standard for virus isolation. This paper reviews the evolution of cell culture methods and demonstrates why cell culture is a preferred method for identification of viruses. In addition, the advantages and disadvantages of both traditional and modern cell culture methods for diagnosis of each type of virus are discussed. Detection of viruses by the novel cell culture methods is considered more accurate and sensitive. However, there is a need to include some more accurate methods such as molecular methods in cell culture for precise identification of viruses.
Short Communication
Coronavirus Disease-19: Summary of 2,370 Contact Investigations of the First 30 Cases in the Republic of Korea
Osong Public Health Res Perspect. 2020;11(2):81-84.   Published online April 30, 2020
DOI: https://doi.org/10.24171/j.phrp.2020.11.2.04
  • 9,719 View
  • 401 Download
  • 45 Citations
AbstractAbstract PDF

Between January 24th and March 10th, a total of 2,370 individuals had contact with the first 30 cases of COVID-19. There were 13 individuals who contracted COVID-19 resulting in a secondary attack rate of 0.55% (95% CI 0.31–0.96). There were 119 household contacts, of which 9 individuals developed COVID-19 resulting in a secondary attack rate of 7.56% (95% CI 3.7–14.26).

Original Article
Investigation of Biofilm Formation and its Association with the Molecular and Clinical Characteristics of Methicillin-resistant Staphylococcus aureus
Jeong-Ok Cha, Jae Il Yoo, Jung Sik Yoo, Hae-Sun Chung, Sun-Hee Park, Hwa Su Kim, Yeong Seon Lee, Gyung Tae Chung
Osong Public Health Res Perspect. 2013;4(5):225-232.   Published online October 31, 2013
DOI: https://doi.org/10.1016/j.phrp.2013.09.001
  • 1,851 View
  • 13 Download
  • 44 Citations
AbstractAbstract PDF
Objectives
To investigate the biofilm-forming related factors against MRSA bloodstream isolates and evaluates their clinical features and treatment outcomes by biofilm production.
Methods
We collected 126 consecutive methicillin-resistant Staphylococcus aureus (MRSA) causing blood stream infections (BSIs) at 10 tertiary hospitals from 2007 to 2009. We investigated biofilm-forming ability using a microtiter plate assay, and molecular characteristics including multilocus sequence typing, staphylococcal cassette chromosome mec and accessory gene regulator types. We compared the clinical characteristics and outcomes of patients infected with biofilm-forming and non-biofilm-forming MRSA isolates.
Results
Of the 126 samples, 86 (68.3%), including 5 strong level (OD570 ≥ 1.0) and 81 weak level (0.2 ≤ OD570 < 1.0), had biofilm-forming capacity. Detection of fibronectinbinding protein in biofilm-forming strains was significantly higher than biofilm non-forming ones (p = 0.001) and three enterotoxin genes (sec-seg-sei) islands had a high frequency regardless of biofilm production. However, biofilm-forming strains were more likely to be multidrug resistant (three or more non-β-lactam antibiotics) than biofilm non-forming ones [79.2% vs. 59.2%, p = 0.015, odds ratio (OR) 2.629, 95% confidence interval (CI) 1.92–5.81]. Clinical features of patients with BSIs caused by biofilm-forming MRSA strains were more likely to be hospital onset [77.9% vs. 60.0%, p = 0.024, OR 2.434, 95% CI 1.11–5.33) and more frequently occurred in patients with use of invasive devices [85.7% vs. 61.2%, p = 0.002, OR 3.879, 95% CI 1.61–8.97]. The other clinical features were compared with the clinical outcomes of the two groups and were not significant (p > 0.05).
Conclusion
Biofilm-forming MRSA strains showed higher frequency of fnbB gene than biofilm non-forming ones and more incidence rates on particular genotypes. And, their patient's features were not significantly different between two groups in this study, except for several clinical factors.

PHRP : Osong Public Health and Research Perspectives