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In this study, the components of microwave-assisted extracts obtained from Thuja orientalis leaves were analyzed, and the cytotoxicity, antibacterial and antiviral activities were evaluated. The predominant components from microwave-assisted extraction were catechin, leucopelargonidin, arecatannin, quinolone, and kaempferol derivatives, which are classified in the fla-vonoid and tannin groups. We observed that the 0.11 mg/mL of extract concentration did not show cytotoxicity in HaCaT cells. The antibacterial activities were tested according to the guidelines of methods for determining the bactericidal activity of antimicrobial agents. The extracts showed 99.9% antibacterial efficiency against gram-positive S. aureus, while the anti-bacterial effect on gram-negative E. coli was insignificant. When the extract concentration and contact time with bacteria were increased, 99.9% antibacterial efficiency was observed for E. coli as well as S. aureus. Following the standard to assess the activity of microbicides against viruses in suspension (ASTM-E1052-20), the antiviral efficiency was more than 99.99% for influenza A (H1N1) and SARS-CoV-2. These results suggest its potential use in antiviral disinfectants, surface coatings, personal protective equipment, and textiles. © 2023 The Korean Society of Industrial and Engineering Chemistry. All rights reserved.
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Research has examined the detrimental effects of the coronavirus disease (COVID-19) pandemic on health and physical fitness in adolescents;however, studies comparing these parameters before and after the COVID-19 outbreak have been scarce. Therefore, this study investigated differences in perceived health status, perceived physical fitness, and participation in physical activity among adolescents in the Republic of Korea before and after the COVID-19 outbreak. We chose a sample of data from 2102 adolescents aged 14-19, collected as part of a national survey by the Republic of Korea Ministry of Culture, Sports, and Tourism from 2019 to 2021. We focused on five items from the survey related to health awareness and physical activity. Although perceived health status was lower in 2021 than in 2019 or 2020, there were no differences in perceived physical fitness during the three years of the study. Regular participation in physical activity was less common in 2020 than in 2019 or 2021. The proportion of adolescents reporting sufficient rest and sleep was lower in 2021 than in 2020. In addition, fewer adolescents reported eating regular meals and engaging in nutritional supplementation in 2021 than in 2019 and 2020. Rates of abstinence from alcohol and smoking cessation were higher in 2021 than in 2019 or 2020. For all three years, adolescents reported the following as the primary reasons for engaging in regular physical activity (in order): "maintenance of mental health", "maintenance of physical health", "help in daily life", and "reduction of medical expenses". In preparation for the post-COVID-19 era, these results highlight the need to prepare measures and countermeasures to promote health and physical activity among adolescents in the Republic of Korea.Copyright ©2023 The Author(s). Published by MRE Press.
ABSTRACT
In this study, the components of microwave-assisted extracts obtained from Thuja orientalis leaves were analyzed, and the cytotoxicity, antibacterial and antiviral activities were evaluated. The predominant components from microwave-assisted extraction were catechin, leucopelargonidin, arecatannin, quinolone, and kaempferol derivatives, which are classified in the fla-vonoid and tannin groups. We observed that the 0.11 mg/mL of extract concentration did not show cytotoxicity in HaCaT cells. The antibacterial activities were tested according to the guidelines of methods for determining the bactericidal activity of antimicrobial agents. The extracts showed 99.9% antibacterial efficiency against gram-positive S. aureus, while the anti-bacterial effect on gram-negative E. coli was insignificant. When the extract concentration and contact time with bacteria were increased, 99.9% antibacterial efficiency was observed for E. coli as well as S. aureus. Following the standard to assess the activity of microbicides against viruses in suspension (ASTM-E1052-20), the antiviral efficiency was more than 99.99% for influenza A (H1N1) and SARS-CoV-2. These results suggest its potential use in antiviral disinfectants, surface coatings, personal protective equipment, and textiles. © 2023 The Korean Society of Industrial and Engineering Chemistry. All rights reserved.
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Background/Aims With widespread implementation of COVID-19 vaccine, there has been concern that it would trigger an immune activation due to its immunogenic properties. There is low-level evidence that patients with rheumatological diagnosis often have a disease flare following COVID-19 vaccination which not only has personal health implications but also wider socioeconomic implications. Inflammatory arthritis patients are classified as vulnerable patients requiring booster vaccinations. Therefore, there is a need to ascertain whether there is a risk of disease flare in this group of patients so as to counsel them appropriately in order to ensure flares are managed in timely manner. This study aims to determine the proportion of patients with inflammatory arthritis who have a flare of their rheumatological disease within 30 days of receiving a COVID-19 vaccine using CRP as a surrogate marker. Methods A retrospective notes review was conducted of patients with inflammatory arthritis within 30 days of their COVID-19 vaccine. An electronic database (DAWN) was used to identify all patients that were currently on a disease-modifying anti-rheumatic drug (DMARD) or biologic therapy. This was then correlated with vaccine data from the National Immunisation and Vaccination system (NIVS) and C-reactive protein (CRP) within 30 days of their vaccination. Results 1620 adults were identified from DAWN databases (mean age 61 years, 64% female). Three types of vaccination were used: AstraZeneca (AZ), BioNTech-Pfizer or Moderna. Vaccine uptake was 1542/1620 (95.2% 1st dose), 1550/1620 (95.7% 2nd dose) and 1437/ 1620 (88.7% 3rd dose). 192/1542 patients (12.5%) had a CRP rise of greater than 10mg/L within 30 days of their vaccine, which was higher than baseline flare rate of 8.6% (p=0.0004). Conclusion Patients with inflammatory arthritis and on DMARDS have high uptake of COVID-19 vaccine (95%) which is greater than the national average. A CRP rise greater than 10mg/L within 30 days of vaccination was observed in roughly 1 in 10 patients in our study population on all three doses which is consistent with other studies in the literature. Our results show statistically significant increase in the rate of disease flare (12.5% compared with baseline rate of 8.6%). However, SARS-CoV-2 infection has been shown many times to be an independent risk factor for rheumatic disease flare ranging from 20-40%. Therefore, patients with inflammatory arthritis should still be encouraged to receive COVID-19 vaccination. To maintain high levels of vaccine uptake, it is important to ensure that patients are aware of the risks of vaccinations and sufficiently safety netted so flares are managed early. As on-going booster vaccinations are planned for rheumatology patients, we recommend further research to better inform and counsel our patients. Furthermore, this study calls for diligence in monitoring patients with inflammatory arthritis for disease flare and for swift intervention to prevent losing disease control.
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Background: Immunocompromised patients with COVID-19 tend to shed viable virus for a prolonged period. Therefore, for moderately or severely immunocompromised patients with COVID-19, CDC recommends an isolation period of at least 20 days and ending isolation in conjunction with serial testing and consultation with an infectious disease specialist. However, data on viral kinetics and risk factors for prolonged viral shedding in these patients are limited. Method(s): From February 1, 2022 to April 1, 2022, we collected weekly saliva samples from immunocompromised patients with COVID-19 admitted to a tertiary hospital in Seoul, South Korea. Genomic and subgenomic RNAs were measured, and virus culture was performed. Result(s): A total of 41 patients were enrolled;29 (70%) were receiving chemotherapy against hematologic malignancies and the remaining 12 (30%) had undergone solid organ transplantation. Of the 41 patients, 14 (34%) had received 3 doses or more of COVID-19 vaccines. Real-time RT-PCR revealed that 7 (17%) were infected with Omicron BA.1, and 33 (80%) with Omicron BA.2. The median duration of viable virus shedding was 4 weeks (IQR 3-6). Patients undergoing B-cell depleting therapy shed viable virus for longer than the comparator (p=0.01). Multivariable analysis showed that 3-dose or more vaccination (HR 0.33, 95% CI 0.12 - 0.93, p = 0.04) and B-cell depleting therapy (HR 12.50, 95% CI 2.44 - 100.00, p = 0.003) independently affected viable virus shedding of SARS-CoV-2. Conclusion(s): Immunocompromised patients with COVID-19 shed viable virus for median 4 weeks. B-cell depleting therapy increases the risk of prolonged viable viral shedding, while completion of a primary vaccine series reduces this risk. Overall distribution of samples according to genomic viral copy number and culture positivity. Red dot indicates positive culture results, whereas blue dot indicated negative culture results. (Figure Presented).
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Dragon fruit is widely grown in Southeast Asia and other tropical or subtropical regions. As a high-value cash crop ideal for exportation, dragon fruit cultivation has boomed during the past decade in southern Vietnam. Light supplementing during the winter months using artificial lighting sources is a widely adopted cultivation technique to boost productivity in the major dragon fruit planting regions of Vietnam. The application of electric lighting at night leads to a significant increase of nighttime light (NTL) observable by satellite sensors. The strong seasonality signal of NTL in dragon fruit cultivation enables identifying dragon fruit plantations using NTL images. We employed Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) monthly nighttime imagery from 2012 to 2019 to extract the growing area of dragon fruit in Bình Thuan Province, the largest dragon fruit growing region of Vietnam. The Breakpoint for Additive Seasonal Trend (B-FAST) analysis was applied to calculate the seasonality of NTL inside the dragon fruit plantations and distinguish them from the background. The results indicated that the dragon fruit cultivation strongly increased after 2014 and reached a plateau after 2017. In recent years, dragon fruit cultivation has experienced a slight decrease due to market fluctuations. We applied a buffer analysis over the largest dragon fruit cultivation area in Bình Thuan to analyze the spatial trend of the expansion of dragon fruit planting. Our results suggest that the dragon fruit cultivation of Bình Thuan has expanded to cover most inter-hill plains, reaching a spatial extent capacity due to the topographical constraints, and thus has begun to encroach into the low-elevation foothill area. In the case of emergency lock-down orders in February 2020 during the COVID-19 pandemic, NTL used for dragon fruit cultivation changed heterogeneously in space and time, driven by market price and shipping limitations far away from the local restrictions. Under the dual rural-urban hot spot situation with strong and contemporary developments of both dragon fruit agriculture and the urban tourism industry, building structures were detected densely in the city and gradually dispersed well into the rural landscape in Bình Thuan. The outcomes of this study will be valuable for local policymakers to better understand of the available area for dragon fruit cultivation and achieve better-coordinated cultivation planning against future fluctuations of the global market while providing insights and new understanding into the dual hot-spot developments valuable for planning rural-urban change strategies. © Springer Nature Switzerland AG 2022. All rights reserved.
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Purpose: The purpose of this study was to investigate the factors affecting the quality of life of cancer patients by examining the de-gree of the COVID-19 pandemic-related depression, anxiety, stress, and treatment-crisis. Methods: Data were collected from 132 cancer patients undergoing surgery, chemotherapy, radiotherapy, and hormone therapy at K University Hospital in D City using a structured questionnaire. The period of data collection was from May 6 to May 28, 2022. The collected data were analyzed using de-scriptive statistics, t-test, ANOVA, Pearson's correlation, and stepwise multiple regression. Results: The mean scores of quality of life, depression, anxiety, stress, and treatment-crisis during the COVID-19 pandemic were 84.64 +/- 29.09, 15.14 +/- 6.49, 4.66 +/- 5.27, 75.83 +/- 17.70, and 78.52 +/- 19.95, respectively. In terms of factors affecting the quality of life related to the COVID-19 pandemic, CO-VID-19 pandemic-related stress (beta=.41,p<.001) appeared to have the greatest impact, followed by COVID-19 pandemic-related treatment-crisis (beta=.28,p=.002), anxiety (beta=.21, p=.002), and gender (beta=.14, p=.009), with a total explanatory power of 67.6%. Con-clusion: To improve the quality of life during the COVID-19 pandemic, COVID-19 pandemic-related stress, treatment-crisis, and anxiety should be periodically monitored and nursing interventions such as education on infection prevention, management, and emotional support programs should be provided to decrease the COVID-19 pandemic-related stress, treatment-crisis, and anxiety.
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Background: Viral infections such as influenza and COVID-19 pose a serious threat to human health, which increases the demand for a new approach to enhance the host immunity. Previous studies showed that exercise activities could enhance the anti-viral neutralizing antibody titers after vaccination. We developed a novel digital device, SAT-008, as a mobile application based on an algorithm to regulate physical activity which are related to boosting innate and adaptive immune systems against virus. SAT-008 aimed to improve the activity of immune cells and the immune response in the body, which can be induced by software -designed -intensity levels of daily physical activities. Method(s): A randomized, open-label, and controlled study was conducted for 13 weeks (Oct 20 to Jan 21). A total of 42 healthy adults aged 24 to 46 years were recruited for this study and 32 among them served for analysis. Subjects were administered a single-dose quadrivalent influenza vaccine. The control group maintained daily life without using SAT-008, while the experimental group used SAT-008 during the study. Result(s): Compared to the control group, the experimental group showed a significant increase in neutralizing antibody titers of antigen subtype B Yamagata lineage after 4 weeks of vaccination and antigen subtype B Victoria lineage after 12 weeks of vaccination (P < 0.05), whereas the controls did not reach a significant level in any antibody titer. In the case of type 'A' influenza, there was no significant difference in neutralizing antibody titers between control and experimental groups. Stimulated NK cells of subjects in the control group decreased significantly between 4 weeks and 12 weeks after the vaccination (P < 0.05) while the subjects in the experimental group slightly increase the NK activity between 4 weeks and 12 weeks after the vaccination, however, there was no significance. The interaction effect was observed between control and experimental groups at weeks 4 and 12 by subsequent analysis (P < 0.05). Conclusion(s): We conclude that a novel approach using the digital device may play an important role to enhance the host immune system to act as a vaccine adjuvant against viral diseases such as influenza.
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Brick-and-mortar retailers are facing increased pressure to innovate to remain competitive against online retailers. In recent years, brick-and-mortar retailers have implemented the addition of curbside service, which allows customers to order ahead and pick up their items without leaving their cars ("click and collect”). While curbside pick-up service has surged 208% during the COVID-19 pandemic (Thomas 2020), it is unclear whether the service will persist in a post-pandemic world. Little empirical research has examined curbside pick-up antecedents or customer behaviors, despite investigations into curbside pick-up being an important issue for marketers (Grewal et al. 2021). This research explores the interplay between customer perceptions of curbside pick-up, time saved by customers, and downstream financial consequences for firms that provide curbside pick-up. Drawing upon the planning fallacy (Kahneman & Tversky 1977), which explains how people underestimate the length of time a task will take to complete, two studies test outcomes at both the firm and customer level. Study 1, an experimental design, examines the impact of itemized versus grouping time saving perceptions for consumers. This study shows that when firms "unpack” the amount of time saved by curbside service, then the perceived value is differentially higher than when time savings are grouped together. Study 2 uses data from a large retailer in the Midwest area of the United States. In Study 2, the authors show that the introduction of curbside service increases the repurchase time for consumers initially, but over time these effects diminish. Overall, the results of these studies show that offering curbside pick-up increases repurchase time for customers, that customers cannot accurately judge how valuable curbside pick-up will be to them, and that firms can convey the value of curbside pick-up via "unpacking" (i.e., itemizing) potential time savings. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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Food hubs assist the economic development of small local farms growing produce sustainably and providing healthy nutrition by aggregating and distributing a diversified range of fresh local food directly to customers. Although food hubs remain niches due to the challenges of growth and implementation, the interest in local and organic food has recently surged, and the demand for online grocery shopping has dramatically increased, especially since the COVID-19 pandemic. This research considers the potential of an online platform for food hubs and examines food practices that include creating and appropriating social networks of food hubs. The study also discusses the implications of the socio-spatial transformation for urban design. With a theoretical framework drawing from social innovation and practice theory, suggesting performance dynamics in practice, this study reviews the current trend of food hubs in the United Kingdom and investigates London-based Growing Communities and Sutton Community Farm, both of which offer community-led veg box schemes. The findings confirm that, as social innovations, community-led food hubs are evolving places for community health and well-being, among other online-based food hubs. This research proposes an evolutionary step for community-led food hubs for social connections. An online platform effectively mobilises resources to connect a diverse local community. More importantly, an online platform interconnected with physical facilities in farm sites and collection points can enhance spatial qualities and capacity and support food access, leading to the sustainable development of urban space. Methodologically, the long-term review of this research confirms the usefulness of the research framework, which revealed evolution in these cases. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
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After the COVID-19 pandemic, cyberattacks are increasing as non-face-to-face environments such as telecommuting and telemedicine proliferate. Cyberattackers exploit vulnerabilities in remote systems and endpoint devices in major enterprises and infrastructures. To counter these attacks, fast detection and response are essential because advanced persistent threat (APT) attacks intelligently infiltrate endpoint devices for long periods and spread to large-scale environments. However, because conventional security systems are signature-based, fast detection of APT attacks is challenging, and it is difficult to respond flexibly to the environment. In this study, we propose an APT fast detection and response technique using open-source tools that improves the efficiency of existing endpoint information protection systems and swiftly detects the APT attack process. Performance test results based on realistic scenarios using the open-source APT attack library and MITER ATT&CK indicated that fast detection was possible with higher accuracy for the early stages of APT attacks in scenarios where endpoint attack detectors are interworking environments. © 2022 The Authors
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Automated sample-to-answer systems that promptly diagnose emerging infectious diseases, such as zoonotic diseases, are crucial to preventing the spread of infectious diseases and future global pandemics. However, automated, rapid, and sensitive diagnostic testing without professionals and sample capacity and type limitations remains unmet needs. Here, we developed an automated sample-to-answer diagnostic system for rapid and accurate detection of emerging infectious diseases from clinical specimens. This integrated system consists of a microfluidic platform for sample preparation and a bio-optical sensor for nucleic acid (NA) amplification/detection. The microfluidic platform concentrates pathogens and NAs in a large sample volume using adipic acid dihydrazide and a low-cost disposable chip. The bio-optical sensor allows label-free, isothermal one-step NA amplification/detection using a ball-lensed optical fiber-based silicon micro-ring resonator sensor. The system is integrated with software to automate testing and perform analysis rapidly and simply;it can distinguish infection status within 80 min. The detection limit of the system (0.96 × 101 PFU) is 10 times more sensitive than conventional methods (0.96 × 102 PFU). Furthermore, we validated the clinical utility of this automated system in various clinical specimens from emerging infectious diseases, including 20 plasma samples for Q fever and 13 (11 nasopharyngeal swabs and 2 saliva) samples for COVID-19. The system showed 100% sensitivity and specificity for detecting 33 samples of emerging infectious diseases, such as Q fever, other febrile diseases, COVID-19, human coronavirus OC43, influenza A, and respiratory syncytial virus A. Therefore, we envision that this automated sample-to-answer diagnostic system will show high potential for diagnosing emerging infectious diseases in various clinical applications. © 2023 Elsevier B.V.
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The coronavirus disease 2019 (COVID-19) pandemic, which began in 2019, has far-reaching ramifications, including economic losses and health challenges that still affect various parts of the world. During our review, we learned that the entire world is working to stop the spread of the SARS-CoV-2 outbreak. We explore ways that may lower the danger of SARS-CoV-2 contamination and useful strategies to avoid the possibility of SARS-CoV-2 spreading through food. While hygienic protocols are required in the food supply sector, cleaning, disinfection, and the avoidance of cross-contamination across food categories and other related goods at different stages of the manufacturing process remain especially important because the virus can survive for long periods of time on inert materials such as food packaging. Furthermore, personal hygiene (regular washing and disinfection), wearing gloves and using masks, garments, and footwear dedicated to maintaining hygiene provide on-site safety for food sector personnel, supply chain intermediaries, and consumers. Restrictions imposed in response to the pandemic (e.g., closure of physical workplaces, canteens, cafes, restaurants, schools, and childcare institutions), changes in household grocery shopping frequency, individuals' perceived risk of COVID-19, income losses due to the pandemic, and sociodemographic factors are among the factors. The conclusions drawn from this study consider the implications of healthy diets, food system resilience, behavior change, and nutritional imbalance for policymakers and food supply chain participants, as well as the antimicrobial effects of vitamins and nutrients. During a public health crisis, people should eat less, necessitating preventive policies and nutritional advice to deal with this.
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This article investigates the changes in South Koreans' acceptance towards multiculturalism and acceptance towards North Korean defectors during the early months of the COVID-19 pandemic in South Korea and potential factors affecting the changes. Individual-level survey data conducted in 2018-2020 were used to compare pre- and post-COVID-19 period. The results demonstrate that the regions with severe local outbreaks during the early COVID-19 pandemic experienced increased hostile attitudes towards multiculturalism and increased discriminatory preference. On the other hand, the pandemic did not affect attitudes towards North Korean defectors. The change may be associated with fear of infection as interaction effects between vulnerability and affected regions after the pandemic were statistically significant. This finding suggests that efforts to disassociate infectious diseases and foreign migrants can mitigate increased hostility towards multiculturalism and foreigners.
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Background: There are limited data on the rates of the waning of antibody levels after two-dose and booster vaccination according to the different platforms of COVID-19 vaccines. Methods: We enrolled healthcare workers (HCWs) in a tertiary care hospital who received homologous two-dose vaccination, followed by a homologous or heterologous booster mRNA vaccine. SARS-CoV-2 S1-specific IgG was measured using ELISA. A linear mixed regression model was used to compare the slope from the peak antibody titer to the lowest antibody titers 3 months after vaccination. Results: A total of 113 HCWs (BNT162b2 (n=48 [42%]), ChAdOx1 nCoV-19 (n=52 [46%]) or mRNA-1273 (n=13 [12%])) were enrolled in this prospective cohort study. More gradual antibody waning was observed over 3 months with the two-dose ChAdOx1 nCoV-19 (ChAdOx1) than with the two-dose BNT162b2 or mRNA-1273 (p< 0.001 and p=0.001, respectively). In addition, homologous mRNA-1273 booster induced a more durable antibody response than homologous BNT162b2 booster (p< 0.001) or heterologous ChAdOx1-BNT162b2 booster (p< 0.001). Conclusion: 2-dose homologous ChAdOx1 vaccination or homologous mRNA-1273 booster appears to induce more-durable antibody responses than 2-dose homologous mRNA vaccination, homologous BNT162b2 booster, or 2-dose ChAdOx1 followed by BNT162b2 booster. Disclosures: All Authors: No reported disclosures.
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Background. There are few data on immune correlation of protection from breakthrough Omicron (B.1.1.529) infection in individuals who received booster vaccines. We thus compared a neutralizing antibody titers against Omicron within the first month after the mRNA booster at the time before omicron wave between healthcare works (HCWs) who experienced Omicron breakthrough infections and HCWs without Omicron infections. Methods. We enrolled HCWs without the history of SARS-CoV-2 infection who agreed with blood sampling 2 weeks after booster vaccination at Asan Medical Center, Seoul, South Korea, between November 2021 and December 2022 (Delta dominant era). We identified breakthrough infections by performing SARS-CoV-2 RT-PCR though nasopharyngeal swab specimen in HCWs who had COVID-19-related symptoms or had known exposure to confirmed SARS-CoV-2-infected patients, between 1 February and 25 April 2022 (Omicron dominant era). SARS-CoV-2 S1-specific IgG antibody titers were measured using enzyme-linked immunosorbent assay (ELISA). Plasma levels of live-virus neutralizing antibodies were measured using a microneutralization assay with SARS-CoV-2 omicron variants. Results. Among 134 HCWs, 69 (52%) received two-dose ChAdOx1 nCoV-19 followed by BNT162b2, 50 (37%) three-dose BNT162b2, and 15 (11%) 3-dose mRNA-1273. Of them, 57 (43%) experienced breakthrough Omicron infection at median 121 days (IQR 99-147) after booster vaccination (breakthrough group), and the remaining 77 (57%) did not experience Omicron infection (non-breakthrough group). There was no significant different in 'peak' SARS-CoV-2 S1-specific IgG level between breakthrough group (median 4484.4 IU/mL) and non-breakthrough group (median 4194.9 IU/mL, p value=0.39). In addition, there was no significant difference in 'peak' neutralizing antibody titer (ID50) against Omicron between breakthrough group (median 2597.9) and non-breakthrough group (median 2597.9, p value=0.86). (Table Presented) Serum samples were obtained from 134 healthcare workers 2 weeks after booster vaccination. Samples were analysed for SARS-CoV-2 S1-specific IgG antibody titers using enzyme-linked immunosorbent assay (ELISA) and plasma levels of live-virus neutralizing antibodies using a microneutralization assay with SARS-CoV-2 omicron variants. There was no significant difference in 'peak' SARS-CoV-2 S1-specific IgG level (A) and 'peak' neutralizing antibody titer (ID50) against Omicron (B) between breakthrough group and non-breakthrough group. Conclusion. We did not find the correlation of neutralizing antibody titers about several months before infection with breakthrough Omicron infections. These data suggest rapidlywaning neutralizing titers to protect mild illnesses or asymptomaticOmicron infections several months after current booster COVID-19 vaccination in HCWs.
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Background. Pregnant women with SARS-CoV-2 infection are known to have a poor prognosis. In addition, the previous meta-analysis revealed that SARS-CoV-2 infection in neonates born from pregnant women with SARS-CoV-2 infection is about 2%. However, there are limited data on the clinical characteristics of pregnant women with SARS-CoV-2 infection and their neonates and the vertical transmission rate in South Korea. Methods. Pregnant women confirmed as SARS-CoV-2 infection were retrospectively reviewed in Asan Medical Center from September 1 2020 to April 26 2022. All neonates from SARS-CoV-2-infected women underwent SARS-CoV-2 PCR within 24 hours after the birth and 48-hour interval if he or she stayed in the hospital. Results. A total of 60 pregnant women gave birth by cesarean section (n=40, 67%) or vaginal delivery (n=20, 33%). Among them, three women gave birth to twins (63 neonates). Delivery was carried out at the average gestational age of 268 days (+/- 14.0), and 9 patients (15%) had underlying diseases. Of these 60 patients, 11 (18%) received COVID-19 vaccination. Pneumonia was confirmed by chest radiograph in 7 patients (12%), and 2 patient (3%) required supplemental oxygen therapy who eventually recovered. The mean weight of 63 newborns was 3137 g (+/- 558), and 8 neonate (13%) was a low-birth weight (< 2500 g), and 12 neonate (19%) was premature (< gestational age 37 weeks). Apgar score was 8.1 points (+/- 1.2) at 1 minute and 9.1 points (+/- 0.8) at 5 minutes. Five neonates (8%) required mechanical ventilation, who eventually recovered. All 63 neonates revealed negative SARS-CoV-2 PCR results with 24 hours after the birth. After 48 hours, 45 newborns exhibited negative SARS-CoV-2 PCR results. So, there was no vertical transmission among 63 neonates (0%, 95% CI 0-6). Conclusion. Our experiences about pregnant women with SARS-CoV-2 infection revealed that obstetric outcomes were favorable and the vertical transmission risk was low. Balancing risks about the infection control of pregnant women and their neonates during the COVID-19 pandemic are needed.
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Background. Centers for Disease Control and Prevention (CDC) recommends 5 to 20 days of isolation for COVID-19 patients depending on symptom duration and severity regardless of genomic PCR results or vaccination history. However, in real clinical practice, more individualized approach is required. We thus developed clinical scoring system to predict viable viral shedding in a given patient by using various factors affecting viable viral shedding. Methods. We prospectively enrolled adult patients with SARS-CoV-2 infection admitted to tertiary hospital and day care center between February 2020 and January 2022. The daily dense respiratory sampling (i.e. saliva, sputum, or nasopharyngeal swabs) during the hospital and day care center stay were obtained. Genomic RNA viral load and viral culture were performed for these samples. Clinical predictors of negative viral culture results were identified using survival analysis and multivariable analysis. Results. A total of 612 samples from 121 patients of varying degrees of severity were obtained. Of these, 494 (81%) samples were saliva, 63 (10%) were nasopharyngeal swab, and the remaining 55 (9%) were sputum. Of these 612 specimens, 154 (25%) samples revealed positive viral culture results. Univariate and multivariable Cox's time varying proportional hazard model revealed that symptom onset day, viral copy number, disease severity, organ transplant recipient, gender, and vaccination status were independently associated with viral culture results. We thus developed the 5-factor model from -3 to 3 points: viral copy number (-3 to 3 points depending on copy number), disease severity (1 point to moderate to critical diseases), organ transplant recipient (2 points), gender (-1 points to male), and vaccination status (-2 points to fully vaccinated status). The predictive culture-negative rates were calculated through the symptom onset day and the score of the day the sample was collected. Conclusion. Our clinical scoring system can provide objective probability of negative culture results in a given COVID-19 patient with genomic viral load, and appears to be useful to decide de-isolation policy depending on individualized factors associated with viable viral shedding beyond simple symptom-based isolation strategy by CDC.
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Background. Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) variant strain B.1.1.529 (omicron) has been less virulent than SARS-CoV-2 B.1.617.2 variant (delta), but there are limited data on the comparison of the cause of death between delta variant and omicron variant infections. We thus compared the causes of death in COVID-19 patients with the delta variant and omicron variant. Methods. We retrospectively reviewed the medical records of adult patients with COVID-19 who were admitted at Asan Medical Center, Seoul, South Korea, between July 2021 and March 2022. We divided into delta-variant dominant period (from July 2021 to December 2021) and omicron-dominant period (from February 2022 to March 2022) with the exclusion of January 2022 because this period was overlapping of delta and omicron variant. The causes of death were classified into COVID-19-associated pneumonia, other causes, and indeterminate cause. Results. A total of 654 patients with COVID-19 were admitted and 42 (6.4%) died during the omicron dominant period (between February and March 2022), while a total of 366 patients with COVID-19 were hospitalized and 42 (11.5%) died during the delta dominant period (between July and December 2021). The primary cause of death was COVID-19-associated pneumonia in 64% (27/42) during the omicron era whereas that was COVID-19-associated pneumonia in 88% (37/42) during the delta era (p value=0.01) (Table 1). Conclusion. We found that about two thirds of patients with omicron variant infection died due to COVID-19, while the majority of patients with delta variant infection died due to COVID-19.