• Journal of Microbiology and Biotechnology
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• v.30 no.10
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• pp.1495-1499
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• 2020

The study of climate and respiratory viral infections using big data may enable the recognition and interpretation of relationships between disease occurrence and climatic variables. In this study, real-time reverse transcription quantitative PCR (qPCR) methods were used to identify Human respiratory coronaviruses (HCoV). infections in patients below 10 years of age with respiratory infections who visited Dankook University Hospital in Cheonan, South Korea, from January 1, 2012, to December 31, 2018. Out of the 9010 patients who underwent respiratory virus real-time reverse transcription qPCR test, 364 tested positive for HCoV infections. Among these 364 patients, 72.8% (n = 265) were below 10 years of age. Data regarding the frequency of infections was used to uncover the seasonal pattern of the two viral strains, which was then compared with local meteorological data for the same time period. HCoV-229E and HCoV-OC43 showed high infection rates in patients below 10 years of age. There was a negative relationship between HCoV-229E and HCoV-OC43 infections with air temperature and wind-chill temperatures. Both HCoV-229E and HCoV-OC43 rates of infection were positively related to atmospheric pressure, while HCoV-229E was also positively associated with particulate matter concentrations. Our results suggest that climatic variables affect the rate in which children below 10 years of age are infected with HCoV. These findings may help to predict when prevention strategies may be most effective.

• Journal of Oral Medicine and Pain
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• v.47 no.1
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• pp.52-61
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• 2022

Purpose: Most cases of oral and maxillofacial infections are usually easily treated by proper diagnosis, elimination of causative factors, and antibiotic therapy. However, the emergence and the increase of multidrug-resistant bacteria make treatment challenging. "ESKAPE" pathogens are the most common opportunistic organisms in nosocomial infections and have resistant to commonly used antibiotics. There are many medical reviews of ESKAPE pathogens, but few in dentistry. This study focuses on oral and maxillofacial infection especially with ESKAPE pathogens. The purpose of this study is to prepare feasible data about tracing and treatment of infection related to pathogens that may be beneficial to clinicians. Methods: A total of 154 patients with oral and maxillofacial infections were reviewed by analyzing retrospectively hospitalized data in the Department of Oral and Maxillofacial surgery, Chosun University Hospital, Korea, past 5 years from January 2014 to December 2018. Based on the medical records and microbiological tests, the results were divided into two groups: infections with ESKAPE pathogens and other bacteria. Results: A total of 22 species were isolated from 154 patients. The proportion of ESKAPE pathogens among all bacterial isolates collected from infected patients was 39.6%. Causative factors, especially in post-operative infection, showed a statistically significant correlation to ESKAPE infections (29 cases). And average of treatment period in ESKAPE group was longer than non-ESKAPE groups. Overall, Klebsiella pneumoniae (60.7%) was the most frequently isolated ESKAPE pathogen. And high antibiotic resistance rates had been detected in the ESKAPE during the five-year period. Conclusions: Infections with ESKAPE pathogens are now a problem that can no longer be overlooked in Dentistry. Based on results of this study, ESKAPE pathogens were highly associated with post-operative or opportunistic infections. Clinicians should be careful about these antibiotic resistant pathogens and use appropriate antibiotics to patients while having dental treatments.

• Pediatric Infection and Vaccine
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• v.19 no.2
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• pp.71-78
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• 2012

Purpose: Human bocavirus (hBoV), a recently discovered virus, has been detected in children with respiratory tract infections worldwide. The aim of this study was to analyze the frequency and molecular phylogeny of hBoV in the respiratory samples of children with acute respiratory tract infections in 2010. Methods: Nasopharyngeal samples were collected from 953 children with lower respiratory tract infections at Severance children's hospital in Korea from January 2010 to December 2010. We applied the multiplex PCR technique for the identification of 12 respiratory viruses from the samples. Among the total specimens, hBoV positive samples were subjected to phylogenetic analysis by sequencing a fragment of the VP1/VP2 gene junction. Results: hBoV was detected in 141 (14.8%) among 953 patients. The 61.7% of hBoV-positive samples were found to co-exist with other respiratory viruses. The results of phylogenetic analysis showed that all 141 hBoV-positive isolates were identified as hBoV 1, revealing a high similarity among the isolates (>98%). Conclusion: hBoV 1 with minimal sequence variations circulated in children with acute respiratory infections during 2010. More research is needed to determine the clinical severity and outcomes of the minimal sequence variations.

• Child Health Nursing Research
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• v.17 no.1
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• pp.1-9
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• 2011

Purpose: The purpose of this study was to investigate the knowledge and practice level of infection managements in child guardians with respiratory infections after H1N1 diffusion of 2009. Methods: The data were collected during February and March 2010 using a self-report questionnaire. The participants were 228 child guardians. Data were analyzed using frequency, percentage, means, SD, t-test, F-test, Pearson correlation coefficients, and Cronbach's alpha with the SPSS 17.0 program. Results: Mean age of the guardians and children were 37.8 years, 4.1 years respectively. For knowledge level of respiratory infections, hand washing method had the highest score and snuffles prevention method, the lowest. For practice level for respiratory infections, environmental hygiene management had the highest score and symptom management, the lowest. Infection management knowledge and practice level had a positively significant correlation in every area. Conclusion: The results indicate the necessity of continual education on infection management, and that the most efficient timing for the education appears be for participants during their first pregnancy or after the woman has delivered her child.

• Pediatric Infection and Vaccine
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• v.30 no.3
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• pp.152-158
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• 2023

Staphylococcus aureus (SA) is a common cause of skin and soft tissue infections. Panton-Valentine leukocidin (PVL) toxin-producing strain of SA has been discovered worldwide and is known to cause serious infections. However, reports of neonatal infections caused by PVL-positive SA are rare. Here, we report a case of severe skin and soft tissue infection caused by PVL-positive SA in a 7-day-old neonate. The patient was admitted to the emergency room with a history of fever for one day, tenderness, and sensation of buttocks heating. The infant presented with fever, tachycardia, poor general health, progressive tenderness, and edema of the buttocks on the day of admission. Ultrasonography and magnetic resonance imaging revealed necrotizing fasciitis involving the skin, soft tissue, and muscles. Specimens drained from the buttock lesions confirmed the presence of PVL-positive methicillin-resistant SA (MRSA), and there was no bacteremia. She recovered after one month of intravenous antibiotics and surgical drainages. One month after discharge, she was rehospitalized for otitis externa and was infected with MRSA again. Considering the PVL-positive strain, the patient was treated with intravenous linezolid and dressing. The patient underwent decolonization therapy in a 0.5% chlorhexidine bath and recovered completely without sequelae. This case suggests that aggressive drainage and antibiotic treatment are essential for PVL-producing MRSA infections, and additional decolonization is needed to prevent recurrence and community spread.

• Tuberculosis and Respiratory Diseases
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• v.80 no.4
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• pp.358-367
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• 2017

Background: Bacterial pneumonia occurring after respiratory viral infection is common. However, the predominant bacterial species causing pneumonia secondary to respiratory viral infections other than influenza remain unknown. The purpose of this study was to know whether the pathogens causing post-viral bacterial pneumonia vary according to the type of respiratory virus. Methods: Study subjects were 5,298 patients, who underwent multiplex real-time polymerase chain reaction for simultaneous detection of respiratory viruses, among who visited the emergency department or outpatient clinic with respiratory symptoms at Ulsan University Hospital between April 2013 and March 2016. The patients' medical records were retrospectively reviewed. Results: A total of 251 clinically significant bacteria were identified in 233 patients with post-viral bacterial pneumonia. Mycoplasma pneumoniae was the most frequent bacterium in patients aged <16 years, regardless of the preceding virus type (p=0.630). In patients aged ${\geq}16years$, the isolated bacteria varied according to the preceding virus type. The major results were as follows (p<0.001): pneumonia in patients with influenza virus (type A/B), rhinovirus, and human metapneumovirus infections was caused by similar bacteria, and the findings indicated that Staphylococcus aureus pneumonia was very common in these patients. In contrast, coronavirus, parainfluenza virus, and respiratory syncytial virus infections were associated with pneumonia caused by gram-negative bacteria. Conclusion: The pathogens causing post-viral bacterial pneumonia vary according to the type of preceding respiratory virus. This information could help in selecting empirical antibiotics in patients with post-viral pneumonia.

• Clinical and Experimental Pediatrics
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• v.49 no.12
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• pp.1287-1295
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• 2006

Purpose : The importance of staphylococcal infections in NICU has been emphasized in terms of increased resistant strains and increased incidence of morbidity and mortality. In this study, we inrestignted the clinical characteristics and risk factors for staphylococcal infections, and looked into sensitivity trends of antibiotics in the era of a high rate of methicillin-resistant staphylococcus aureus (MRSA) in our society. Methods : This study included 240 neonates with positive blood, urine and other sites cultures for staphylococci who were admitted to NICU of Hanil General Hospital and Kyunghee University Hospital from January 2000 to December 2004. The analyses included clinical characteristics of staphylococcal infections and the relationship of incidence rate among various factors, including invasive procedures. Results : For 5 years, 3,593 patients were hospitalized in the NICU and 7,481 specimens were cultured from blood, urine, and other sites. During the study period, staphylococci were isolated from 240 patients, of whom 88 patients had MRSA, 41 patients methcillin sensitive staphylococcus aureus (MSSA), 63 patients S. epidermidis, 48 patients coagulase-negative staphylococcus (CNS) except S. epidermidis infections. The risk factors associated with staphylococcal infections were less than 37 weeks of gestational age, less than 7 on a 5 minutes Apgar score, receiving TPN, applied mechanical ventilation, use of central venous catheters and other tubes. The sensitivity to vancomycin was 100 percent. A relatively high sensitivity against teicoplanin, trimethoprim-sulfamethoxazole, chloramphenicol, clindamycin and low sensitivity against gentamicin and erythromycin were shown. Conclusion : To reduce staphylococcal infections in NICU, we need to monitor and manage premature neonates from the beginning of the birth process and to avoid as many invasive procedures as possible in NICU. Considering MRSA, control of preceding factors and early use of appropriate antibiotics is expected to reduce the morbidity and mortality caused by MRSA infections.

• Safety and Health at Work
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• v.6 no.4
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• pp.353-356
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• 2015

Background: In 2012, the Alaska Section of Epidemiology investigated personnel potentially exposed to a Brucella suis isolate as it transited through three laboratories. Methods: We summarize the first implementation of the United States Centers for Disease Control and Prevention 2013 revised recommendations for monitoring such exposures: (1) risk classification; (2) antimicrobial postexposure prophylaxis; (3) serologic monitoring; and (4) symptom surveillance. Results: Over 30 people were assessed for exposure and subsequently monitored for development of illness. No cases of laboratory-associated brucellosis occurred. Changes were made to gaps in laboratory biosafety practices that had been identified in the investigation. Conclusion: Achieving full compliance for the precise schedule of serologic monitoring was challenging and resource intensive for the laboratory performing testing. More refined exposure assessments could inform decision making for follow-up to maximize likelihood of detecting persons at risk while not overtaxing resources.

• Biomedical Science Letters
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• v.29 no.4
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• pp.220-230
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• 2023

Identification of the pathogens causing infection is important in terms of patient's health management and infection control. Synovial fluids could be used as clinical samples to detect causative pathogens of prosthetic joint infections (PJIs) using molecular diagnostic assays, therefore, normalization and validation of clinical samples are necessary. Microbial culture is considered the gold standard for all infections, including PJIs. Recently, molecular diagnostic methods have been developed to overcome the limitation of microbial culture. Therefore, guideline for validating clinical samples to provide reliable results of molecular diagnostic assays for infectious diseases is required in clinical field. The present study aimed to develop an accurate validating method of synovial fluid clinical samples using GAPDH gene as an internal control to perform the quantitative PCR TaqMan probe assay to detect pathogens causing PJIs.

• Parasites, Hosts and Diseases
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• v.56 no.2
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• pp.147-152
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• 2018

This prospective study was aimed to detect acute and chronic ocular toxoplasmosis by comparison of anti-Toxoplasma gondii IgM and IgG antibody levels and IgG avidity test. One hundred and seventeen patients with ocular toxoplasmosis (OT) who referred to the Farabi Eye Hospital, Tehran, Iran were included in this study. Of the patients, 77 cases were positive for anti-T. gondii IgG, and 8 cases were positive for anti-T. gondii IgM. IgG avidity test revealed 11, 4, and 102 cases were low, intermediate, and high, respectively, and 6.8% and 9.4% of cases were positive for IgM and IgG avidity tests, respectively (P=0.632). Agreement (Kappa value) between paired tests IgG-IgM, IgG-IgG avidity, and IgM-IgG avidity was 0.080, 0.099, and 0.721, respectively (P<0.05). This study showed that conventional serologic tests (IgM and IgG levels) and IgG avidity correlate well each other and can be used to differentiate recent infections from old OT. It seems that reactivated old infections rather than recently acquired infections are majority of Iranian OT patients.