• Pediatric Infection and Vaccine
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• v.17 no.1
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• pp.1-8
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• 2010

Purpose : Recently, vancomycin-resistant enterococci (VRE) have become one of the major nosocomial pathogens in Korea. However, there have been few studies on the epidemiology of VRE colonization among neonates. In this study, we investigated the prevalence of VRE colonization, risk factors for VRE, and how to control the spread of VRE infection in the Neonatal Intensive Care Unit (NICU) of Pusan National University Hospital (PNUH). Methods : We retrospectively reviewed medical records of 192 neonates who were admitted to the NICU of PNUH from March 2006 to March 2007. Surveillance cultures from rectal swabs for detecting VRE were obtained weekly during the study period. We analyzed the prevalence of VRE and various risk factors. Results : The rate of VRE colonization among NICU patients was 25% (48/192). Thirty five of these VRE colonized patients were transferred to the NICU from other local hospitals. Compared with the non-VRE group, the risk factors associated with VRE colonization were lower birth weight, congenital heart disease, applied mechanical ventilation, use of a central venous catheter, chest tubing, a history of surgery, and use of antibiotics. Conclusion : VRE colonization among patients admitted to the NICU is rapidly increasing. Monitoring and managing premature neonates from the beginning of the birth process, avoiding many invasive procedures, avoiding antibiotics such as vancomycin and third generation cephalosporin are important for preventing the emergence and spread of VRE colonization in the NICU.

• Clinical and Experimental Pediatrics
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• v.50 no.2
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• pp.157-162
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• 2007

Purpose : The purpose of this study was to analyze the epidemiology, causative organism, clinical manifestation and prognosis of bacterial meningitis for children after the introduction of Haemophilus influenzae type b (Hib) vaccine in Daejeon and Chungcheong area. Methods : We analyzed retrospectively 53 medical records who had been diagnosed with bacterial meningitis at 10 general or university hospitals in Daejeon and Chungcheong area. All patients aged 1 month-14 years admitted between January 2001 through December 2005. Results : During the 5-year study period, 40 of all cases were positive for bacterial growth. Of the 40 cases that were CSF culture-proven bacterial meningitis, Streptococcus peumoniae was the most common bacteria for 17 (32.1%) of all cases, followed by H. influenzae for 10 (18.9%), Neisseria meningitidis for 3 (5.7%). In this study, the most common clinical manifestation is fever, accompanied by all cases. CSF leukocyte count was more than $100/mm^3$ in 45 (84.1%) cases. CSF glucose concentration was less than 50 mg/dL in 42 (79.2%) cases and protein concentration was more than 45 mg/dL in 49 (92.5%) cases. 45 of all cases made a recovery after treatment and were discharged. Most common complication after treatment is subdural effusion (19.0%) and hearing disturbance (9.4%). Conclusion : The most common organism of culture-proven bacterial meningitis in the children beyond neonatal period was S. pneumoniae. Continued surveillance studies were demanded to know the altered incidence of bacterial meningitis, because we expect the incidence of S. pneumoniae meninigitis will be on the decrease after more active innoculation of pneumococcal protein conjugate vaccine.

• Sleep Medicine and Psychophysiology
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• v.8 no.2
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• pp.129-137
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• 2001

Objectives: The purpose of this study is to investigate the effects of 38-hour sleep deprivation on fine motor performance. The Motor Performance Series (MPS) in the Vienna Test System (computerized neurocognitive function tests) was used in this study. Methods: Twenty four subjects participated in this study. Subjects had no past history of psychiatric disorders and physical illness. Subjects had normal sleep-waking cycle without current sleep disturbances and were all right-handed (Annett's Hand Preference Questionnaire: above +9 points). To minimize the learning effects, familiarization with the Vienna Test System was performed one day before the study. Subjects were to get up at 6:00 in the morning after getting enough sleep according to his or her usual sleep-wake cycle. After awakening, subjects remained awake for 38 hours under continuous surveillance. During two consecutive study days, the subjects tested MPS at 7 AM and 7 PM each day, which means the MPS was done four times in total. During the experiment, anything that could affect the subjects' sleep such as coffee, tea, alcohol, a nap, tiring sports, and all medications were prohibited. Results: In MPS, the fine motor functions of both hands decreased after 38 hours of sleep deprivation. The decrement in motor performance was prominent in the dominant right hand. In the right hand, the total number of tapping was reduced (p<.005), and the number of misses (p<.05) and the length of misses (p<.05) of line tracking, the total length of inserting a short pin (p<.01), the total length of inserting a long pin (p<.05), and the number of misses in aiming (p<.05) increased. Such performance decrement was distinct in the morning sessions. Conclusions: These results suggest that fine motor performance decrement during sleep deprivation is predominant in the right hand, which exerts maximal motor function. The finding of decrement in motor function in tapping during sleep deprivation also suggested that the time required for exhaustion of muscles is shortened during sleep deprivation. More deterioration of motor performance was shown in the morning, which could be explained as circadian rhythm effects.

• Pediatric Infection and Vaccine
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• v.28 no.2
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• pp.101-109
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• 2021

Purpose: Common human coronaviruses (HCoVs) are relatively understudied due to the mild nature of HCoV infection. Given the lack of local epidemiology data on common HCoVs, we aimed to describe clinical and epidemiological characteristics of common HCoVs in children. Methods: Respiratory viral test results from 9,589 respiratory samples from Seoul National University Children's Hospital were analyzed from January 2015 to December 2019. Viral detection was done by the multiplex reverse transcription polymerase chain reaction. Demographics and clinical diagnosis were collected for previously healthy children tested positive for HCoVs. Results: Of the 9,589 samples tested, 1 or more respiratory viruses were detected from 5,017 (52.3%) samples and 463 (4.8%) samples were positive for HCoVs (OC43 2.8%, NL63 1.4%, 229E 0.7%). All 3 types co-circulated during winter months (November to February) with some variation by type. HCoV-OC43 was the most prevalent every winter season. HCoV-NL63 showed alternate peaks in late winter (January to March) and early winter (November to February). HCoV-229E had smaller peaks every other winter. Forty-one percent of HCoV-positive samples were co-detected with additional viruses; human rhinovirus 13.2%, respiratory syncytial virus 13.0%, influenza virus 4.3%. Common clinical diagnosis was upper respiratory tract infection (60.0%) followed by pneumonia (14.8%), croup (8.1%), and bronchiolitis (6.7%). Croup accounted for 17.0% of HCoV-NL63-positive children. Conclusions: This study described clinical and epidemiological characteristics of common HCoVs (OC43, NL63, 229E) in children. Continuing surveillance, perhaps by adding HKU1 in the diagnostic panel can further elucidate the spectrum of common HCoV infections in children.

• Annals of Clinical Microbiology
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• v.22 no.1
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• pp.9-13
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• 2019

Background: The isolation of carbapenemase-producing Enterobacteriaceae (CPE) has become increasingly common. Continuous surveillance for these organisms is essential because their infections are closely related to outbreaks of illness and are associated with high mortality rates. The aim of this study was to develop and evaluate multiplex PCR as a means of detecting several important CPE genes simultaneously. Methods: We aimed to develop a multiplex PCR that could detect seven CPE genes simultaneously. The multiplex PCR was composed of seven primer sets for the detection of KPC, IMP, VIM, NDM-1, GES, OXA-23, and OXA-48. We designed different PCR product sizes of at least 100 bp. We evaluated the performance of this new test using 69 CPE-positive clinical isolates. Also, we confirmed the specificity to rule out false-positive reactions by using 71 carbapenem-susceptible clinical strains. Results: A total of 69 CPE clinical isolates showed positive results and were correctly identified as KPC (N=14), IMP (N=13), OXA-23 (N=12), OXA-48 (N=11), VIM (N=9), GES (N=5), and NDM (N=5) by the multiplex PCR. All 71 carbapenem-susceptible clinical isolates, including Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa, showed negative results. Conclusion: This multiplex PCR can detect seven CPE genes at a time and will be useful in clinical laboratories.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.102-108
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• 1984

This paper is the result of adult female mosquito and larval collection in U.S. Army Installations in Korea from 1979 to 1983. New Jersey light traps were operated for adult collection from May to October. The primary concern of this surveillance is to determine when to recommend insecticide spraying for mosquito control in the Army areas. The 5th Preventive Medicine Unit have developed an "index" level of female mosquitoes in a light trap similar to other U.S. Army Agencies in other parts of the world. When 10 female mosquitoes are reached on two consecutive trap-night, or 5 known vector females are collected, fogging is recommended in the trap areas. 1. Mosquito collections were conducted in 12 U.S. Army areas by operating 39 New Jersey light traps. Mosquitoes collected from the areas were identified to be 17 species comprising 3 genera. Anopheles sinensis (40%), Culex tritaeniorhynchus (31%), Aedes vexans nipponii (19 %) and Culex pipiens pallens (10%) appeared to be the most common species in the areas. 2. The species, population density and monthly appearance of adult mosquitoes were found to be almost the same in the all provinces involved. And Japanese Encephalitis vector mosquitoes, Culex tritaeniorhynchus, showed their seasonal fluctuation from July to September with a peak in August each year. 3. Larval habitats confirmed in the Army areas were categorized into 16 types as shown in Table 3. The mosquito larvae collected in those habitats were identified to be 15 species representing 4 genera. Most breeding sites in the Army areas were those which are activated during the wet season. 4. More mosquitoes were collected from the Kyungki Province than from the other Provinces. The reason for more collection of mosquitoes from military installations in the Kyungki Province appears to be the geographic characteristics surrounded by rice fields, marshes and other stagnant water areas.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.909-913
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• 2013

Purpose: The liver is the organ to which colorectal carcinomas (CRCs) most commonly metastasize, and surgical resection has been established as the most effective and potentially curative treatment for CRC with liver metastasis (LM). Therefore, surveillance of LM is vital for improvement of prognosis of CRC patients. In this study, we aimed to explore the potential value of carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), and marker enzymes in indicating LM with CRC. Methods: Three groups of eligible patients with metastatic cancers were retrospectively included: CRC patients with LM (CRC-LM) or without LM (CRC-NLM), and non-CRC patients with LM (NCRC-LM). All metastatic lesions were identified by CT or MRI. Data on characteristics of the patients, the primary site, the locations of metastasis, CA 19-9, CEA, and biochemical parameters were collected for analysis. Results: A total of 493 patients were retrospectively included. More alcohol consumption was found in CRC-LM than CRC-NLM. Some biochemical enzymes were found to be significantly higher in groups with LM than without (CRC-LM or NCRC-LM v.s CRC-NLM). Both CEA and CA 19-9 were much higher in CRC-LM than CRC-NLM or NCRC-LM. For CRC patients, CA 19-9, ${\gamma}$-glutamyl transpeptidase, CEA and alcohol consumption were identified as independent factors associated with LM. Conclusion: Our analysis suggested the CA 19-9 might be a potential valuable indicator for LM of CRC in the clinic.

• Tuberculosis and Respiratory Diseases
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• v.65 no.4
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• pp.269-276
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• 2008

Background: Although the prevalence of tuberculosis infections (PTBI) is one of the basic epidemiologic indices, no survey has been carried out since 1995 because the nation-wide tuberculosis prevalence survey was changed to a surveillance system. Subjects without a BCG scar are examined in a tuberculin survey. However, it is very difficult to select these subjects under high vaccination coverage. It is important to evaluate the impact of BCG vaccinations on the tuberculin response and estimate the PTBI regardless of the BCG vaccination status. Methods: A nation-wide, school-based cross-sectional tuberculin survey was carried out among first graders in elementary school in 2006. A total of 5,148 children in 40 schools were selected by quota sampling. Tuberculin testing with 0.1 ml of two tuberculin units of PPD RT23 was carried out on 4,018 children. The maximum transverse diameter of induration was measured 48 to 72 hours later. The presence of a BCG scar was checked separately. Results: There were no BCG scars in 6.3% of the subjects. The mean induration size of tuberculin testing was $3.7{\pm}4.4mm$, which included 1,882 (46.8%) subjects with an induration size of 0 mm. The PTBI was 10.9% (439 subjects) using a cut-off point of ${\geq}10mm$ (conventional method). The annual risk of tuberculosis infections (ARTI) was 1.9% when the mean age of the subjects was assumed to be 6 years. There was no difference in the PTBI according to the presence or absence of a BCG scar [11.2% vs 7.6% (OR: 1.54, 95% CI: 0.98~2.43)]. Using a mirror image technique with 16 mm as the cut-off point, the PTBI and ARTI had decreased to 2.4% and 0.4% respectively. Conclusion: PTBI and ARTI, as estimated by conventional methods, appear to be high among BCG vaccinated children. A mirror image technique is more suitable for estimating the indices in a country with an intermediate burden of tuberculosis than the conventional method.

• Journal of Life Science
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• v.26 no.8
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• pp.911-920
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• 2016

Norovirus is the most common causative agent of acute gastroenteritis. This study was carried out to investigate molecular epidemiology of norovirus infections from outbreaks in Busan from 2012 to 2015. Total of 581 stool specimens were collected from diarrhea patients in outbreaks in Busan, 71 samples were resulted in positive to norovirus. The data were analyzed according to seasonality, patient, age and gender. Noroviruses were detected most frequently during the winter season from November (25.4%) to February (28.2%). The age group from teens was the most susceptible to norovirus infections. To obtain the molecular genetic information of norovirus, we performed sequencing analyses of the strains detected. Norovirus genotypes have been reported to show high genetic diversity. Four kinds of GI genotypes (GI-1, GI-2, GI-3, GI-5) and five kinds of GII genotypes (GII-1, GII-4, GII-5, GII-6, GII-17) were indentified in outbreaks in Busan. Other previous studies have shown that GII-4 is the most predominant circulating in Korea and worldwide. The most prevalent norovirus genotypes of each year were GII-6 in 2012, GII-6 in 2013, GII-4 in 2014 and GII-6 in 2015. Except for 2014, GII-6 genotype was the most prevalent and predominant in Busan. We described the epidemiological analysis of the noroviruses in outbreaks in Busan. The result of this study will contribute to update the epidemiological data and improve hygiene and public health via sustainable surveillance.

• Pediatric Infection and Vaccine
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• v.21 no.3
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• pp.181-190
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• 2014

Purpose: This study was performed to investigate the epidemiological trend of rotavirus acute gastroenteritis (RV-AGE) in children. Methods: A retrospective review was performed in patients (1 month to 18 years of age) with acute gastroenteritis at KEPCO Medical Center from September 2004 to August 2013. Comparative analyses were performed based on periods: pre-vaccine (2004-2006) and post-vaccine (2008-2012) in all patients; 2004-2006 (period A), 2007-2009 (period B) and 2010-2012 (period C) in patients under 5 years of age. Results: Proportion of RV-AGE decreased from 25.0% (337/1,346) in pre-vaccine period to 20.8% (459/2,210) in post-vaccine period (rate ratio (RR), 0.83 [95% CI, 0.73-0.93]; P=0.0029). The median age of patients with RV-AGE in post-vaccine period (2.6 years) was significantly (P<0.0001) higher than that in pre-vaccine period (1.6 years). In patients hospitalized with AGE, proportion of RV-AGE was significantly reduced in patients 6 to 23 months old (RR, 0.62 [95% CI, 0.51-0.75]; P<0.0001). Significant decline in proportion of RV-AGE was observed in patients under 5 years of age: period A, 26.9% (308/1,144); period B, 22.7% (295/1,299); period C, 20.6% (186/902) (P =0.0007). After the introduction of rotavirus vaccine, a significant decreasing trend of RV-AGE proportion was observed in patients 6 to 11 months old (P =0.0018) and 12 to 23 months old (P =0.0152). Conclusion: Decrease in RV-AGE proportion and increase in age of patients with RV-AGE were observed after the introduction of rotavirus vaccine in this single center study. Continued and systematic surveillance is needed to assess the impact of rotavirus vaccine.