A cluster of severe pneumonia of unknown etiology in Wuhan City, Hubei province in China emerged in December 2019. A novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was isolated from lower respiratory tract sample as the causative agent. The current outbreak of infections with SARS-CoV-2 is termed coronavirus disease 2019 (COVID-19) by the World Health Organization (WHO). COVID-19 rapidly spread into at least 114 countries and killed more than 4,000 people by March 11, 2020. WHO officially declared COVID-19 a pandemic on March 11, 2020. There have been 2 novel coronavirus outbreaks in the past 2 decades. The outbreak of severe acute respiratory syndrome (SARS) in 2002-2003 caused by SARS-CoV had a case fatality rate of around 10% (8,098 confirmed cases and 774 deaths), while Middle East respiratory syndrome (MERS) caused by MERS-CoV killed 858 people out of a total 2,499 confirmed cases between 2012 and 2019. The purpose of this review is to summarize known-to-date information about SARS-CoV-2, transmission of SARS-CoV-2, and clinical features of COVID-19.

To determine the epidemiologic features and clinical outcomes of bloodstream infections caused by extended-spectrum ␤-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae isolates, cases of bacteremia caused by these organisms in children were analyzed retrospectively. Among the 157 blood isolates recovered from 1993 to 1998 at the Seoul National University Children's Hospital, the prevalence of ESBL production was 17.9% among the E. coli isolates and 52.9% among the K. pneumoniae isolates. The commonest ESBLs were SHV-2a and TEM-52. A novel ESBL, TEM-88, was identified. Pulsed-field gel electrophoresis analysis of the ESBL-producing organisms showed extensive diversity in clonality. The medical records of 142 episodes were reviewed. The risk factors for bloodstream infection with ESBL-producing organisms were prior hospitalization, prior use of oxyimino-cephalosporins, and admission to an intensive care unit within the previous month. There was no difference in clinical severity between patients infected with ESBL-producing strains (the ESBL group) and those infected with ESBL-nonproducing strains (the non-ESBL group) at the time of presentation. However, the overall fatality rate for the ESBL group was significantly higher than that for the non-ESBL group: 12 of 45 (26.7%) versus 5 of 87 (5.7%) (P ‫؍‬ 0.001). In a subset analysis of patients treated with extended-spectrum cephalosporins with or without an aminoglycoside, favorable response rates were significantly higher in the non-ESBL group at the 3rd day (6 of 17 versus 33 of 51; P ‫؍‬ 0.035), the 5th day (6 of 17 versus 36 of 50; P < 0.05), and the end of therapy (9 of 17 versus 47 of 50; P < 0.001). In conclusion, the ESBL production of the infecting organisms has a significant impact on the clinical course and survival of pediatric patients with bacteremia caused by E. coli and K. pneumoniae.Escherichia coli and Klebsiella pneumoniae are leading causes of serious infections in neonates, neutropenic cancer patients, and other patients with underlying diseases. These bacteria had been uniformly susceptible to oxyimino-␤-lactam antimicrobials. However, since the initial description of extended-spectrum ␤-lactamase (ESBL) production by K. pneumoniae strains in 1983 (18) and E. coli strains in 1987 (3), strains of E. coli and K. pneumoniae that are resistant to broadspectrum cephalosporins are increasingly being recognized (6, 14). There have been many reports of outbreaks caused by these organisms in cancer centers, pediatric and geriatric wards, and hospitalized nursing home patients. However, epidemiologic descriptions of bloodstream infections caused by ESBL-producing E. coli and K. pneumoniae are limited (32,36), and clinical data regarding treatment are further limited (2,31,35,36). At present, carbapenems are recommended for the treatment of infections caused by ESBL-producing organisms. However, this recommendation is primarily based on the in vitro effect (12), the results of animal experiments (33), and only very limited clinical da...

A cluster of severe pneumonia of unknown etiology in Wuhan City, Hubei province in China emerged in December 2019. A novel coronavirus named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was isolated from lower respiratory tract sample as the causative agent. The current outbreak of infections with SARS-CoV-2 is termed Coronavirus Disease 2019 (COVID-19) by the World Health Organization (WHO). COVID-19 rapidly spread into at least 114 countries and killed more than 4,000 people by March 11 2020. WHO officially declared COVID-19 a pandemic on March 11, 2020. There have been 2 novel coronavirus outbreaks in the past 2 decades. The outbreak of severe acute respiratory syndrome (SARS) in 2002–2003 caused by SARS-CoV had a case fatality rate of around 10% (8,098 confirmed cases and 774 deaths), while Middle East respiratory syndrome (MERS) caused by MERSCoV killed 861 people out of a total 2,502 confirmed cases between 2012 and 2019. The purpose of this review is to summarize known-to-date information about SARS-CoV-2, transmission of SARS-CoV-2, and clinical features.

IMPORTANCE There is limited information describing the full spectrum of coronavirus disease 2019 (COVID-19) and the duration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA detection in children. OBJECTIVE To analyze the full clinical course and the duration of SARS-CoV-2 RNA detectability in children confirmed with COVID-19 in the Republic of Korea, where rigorous public health interventions have been implemented. DESIGN, SETTING, AND PARTICIPANTS This case series of children with COVID-19 was conducted in 20 hospitals and 2 nonhospital isolation facilities across the country from February 18, 2020, to March 31, 2020. Children younger than 19 years who had COVID-19 were included. EXPOSURES Confirmed COVID-19, detected via SARS-CoV-2 RNA in a combined nasopharyngeal and oropharyngeal swab or sputum by real-time reverse transcriptionpolymerase chain reaction. MAIN OUTCOMES AND MEASURES Clinical manifestations during the observation period, including the time and duration of symptom occurrence. The duration of SARS-CoV-2 RNA detection was also analyzed. RESULTS A total of 91 children with COVID-19 were included (median [range] age, 11 [0-18] years; 53 boys [58%]). Twenty children (22%) were asymptomatic during the entire observation period. Among 71 symptomatic cases, 47 children (66%) had unrecognized symptoms before diagnosis, 18 (25%) developed symptoms after diagnosis, and only 6 (9%) were diagnosed at the time of symptom onset. Twenty-two children (24%) had lower respiratory tract infections. The mean (SD) duration of the presence of SARS-CoV-2 RNA in upper respiratory samples was 17.6 (6.7) days. Virus RNA was detected for a mean (SD) of 14.1 (7.7) days in asymptomatic individuals. There was no difference in the duration of virus RNA detection between children with upper respiratory tract infections and lower respiratory tract infections (mean [SD], 18.7 [5.8] days vs 19.9 [5.6] days; P = .54). Fourteen children (15%) were treated with lopinavir-ritonavir and/or hydroxychloroquine. All recovered, without any fatal cases. CONCLUSIONS AND RELEVANCE In this case series study, inapparent infections in children may have been associated with silent COVID-19 transmission in the community. Heightened surveillance using laboratory screening will allow detection in children with unrecognized SARS-CoV-2 infection.

Background Coronavirus disease 2019 (COVID-19) vaccination is necessary to reach herd immunity and essential for mitigating the spread of the pandemic. In May 2021, the US FDA and the EU have expanded the emergency use authorization for a COVID-19 vaccine to children aged 12 to 15. The aim of this study was to investigate parental acceptability of COVID-19 vaccination for their children, factors affecting their acceptability, and children's perceptions of COVID-19 vaccines in Republic of Korea. Methods We conducted a questionnaire survey at two tertiary hospitals from May 25, 2021 to June 3, 2021. Subjects were parents having children under 18 years and children aged 10–18 years. Results Two hundred twenty-six parents and 117 children aged 10–18 years were included in the final analysis. Overall, 76.5% and 64.2% of parents intended to get vaccinated against COVID-19 and intended to have their children vaccinated, respectively. However, only 49.6% of children responded that they would get COVID-19 vaccination. In the multivariate analysis, high confidence in the safety of COVID-19 vaccines (adjusted odds ratio [AOR], 4.87; 95% confidence interval [CI], 1.32–24.12), parents' willingness to vaccinate themselves (AOR, 19.42; 95% CI, 6.85–64.00), and awareness of the need to vaccinate children against COVID-19 (AOR, 13.15; 95% CI, 4.77–41.27) were associated with positive factors intention to vaccinate their children. Conclusion This study provides insight into how parents think about the COVID-19 vaccine for their children in South Korea. Our findings could be referenced in establishing a policy for childhood COVID-19 vaccination in the future.