Management of centralized transition ward in a large general hospital in Shanghai during the epidemic caused by severe acute respiratory syndrome coronavirus 2 omicron variant infection.

The epidemic of coronavirus disease 2019 (COVID-19) has seriously affected people's normal work, life, and medical treatment. Since Mar. 2022, there has been a pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant in Shanghai. In order to meet the needs of hospitalization for patients, and at the same time for better control of epidemic and nosocomial infections, a large hospital in Shanghai innovatively set up a centralized transition ward in the hospital, and established scientific rules of medical work, regulations for prevention of nosocomial infections and efficient norms for patient admission. During the operation of the ward, a total of 211 patients were treated and one of the patients was confirmed of COVID-19 recurrence. All work was carried out methodically, and neither hospitalized patients nor medical staff had nosocomial infection of COVID-19. The preparation, operation and management of the central transition ward in our hospital are summarized here to provide guidance and reference for general hospitals to carry out similar work under the epidemic.Copyright © 2022, Second Military Medical University Press. All rights reserved.

Traditional Chinese Medicine Syndrome Differentiation of Delta and Omicron Variants of SARS-CoV-2 Carriers in Changsha,Hunan.

Objective: To summarize and compare the main traditional Chinese medicineTCMsyndromes of Delta and Omicron variants of severe acute respiratory syndrome coronavirus 2SARS-CoV-2 carriers to provide references for the syndrome evolution and syndrome differentiation of SARS-CoV-2 infection. Method(s):The TCM medical records of imported and local cases of infection with Delta and Omicron variants of SARS-CoV-2 in Changsha since September 23,2021 to March 27,2022 were collected,including 18 Delta variant cases and 36 Omicron variant cases. Their TCM diagnosis information and TCM pathogenesis were analyzed and compared. Result(s): The common manifestations in Delta variant cases were cough,fever,chest distress/shortness of breath,sore muscles,nausea,dry mouth,dry or sore throat,thick and greasy tongue coating,and rapid and slippery pulse. The predominant pathogenesis was dampness-heat in the upper-energizer and heat stagnation in the lesser Yang combined with dampness. The occurrence of chest distress/shortness of breath,greasy tongue coating,slippery pulse,and the proportion of dampness-heat in the upper-energizer syndrome were higher in Delta variant cases than in Omicron variant cases P<0.05. The common manifestations in Omicron variant cases were itchy and sore throat,nasal congestion,running nose,fever,mild aversion to cold,dry mouth,dizziness,slightly reddish tongue with thin white coating,and rapid or wiry pulse. The predominant pathogenesis was wind-dryness invading defensive exterior,and heat stagnation in the lesser Yang. The occurrence of white-coated tongue and the proportion of wind-dryness invading defensive exterior syndrome were higher in Omicron variant cases than in Delta variant casesP<0.05. Conclusion(s): There are certain differences in TCM syndromes and the corresponding pathogenesis between Delta variant and Omicron variant cases in Changsha,Hunan. The Delta variant of SARS-COV-2 tends to induce dampness-heat syndrome, whereas Omicron variant infection tends to elicit wind-dampness syndrome,which is expected to provide a reference for the pathogenesis evolution of SARS-COV-2 infection.Copyright © 2022, China Academy of Chinese Medical Sciences Institute of Chinese Materia Medica. All rights reserved.

Thoughts on diagnosis and treatment plan of patients infected with severe acute respiratory syndrome coronavirus 2 omicron variant in large shelter hospitals in Shanghai.

The epidemic caused by the infection of severe acute respiratory syndrome coronavirus 2 omicron variant broke out in Shanghai in Mar. 2022. Omicron variant has characteristics such as strong concealment and rapid transmission, resulting in significant differences between the current round of epidemic and that in Wuhan. The number of infected patients (mainly asymptomatic infected patients) increased rapidly in a short term. Based on dynamic zero policy, shelter hospitals were set up in time in Shanghai to treat the patients. It is suggested that medical resources and patient characteristics should be taken into account in the independent cabin of a shelter hospital with more than 10 000 beds, and the clinical medical practice should be divided to 5 modes (universal education and management, community outpatient clinic, ward duty, emergency rescue, and temporary observation and transport) to optimize the allocation of medical resources, so as to further enhance the treatment capacity and efficiency of shelter hospitals.Copyright © 2022, Second Military Medical University Press. All rights reserved.

Myocardium damage and electrocardiogram characteristics of patients infected with SARS-CoV-2 Omicron variant in Zhuhai

Aim To explore the myocardial damage, abnormal electrocardiogram characteristics of patients infected with SARS-CoV-2 Omicron variant in Zhuhai. Methods 84 patients with SARS-CoV-2 Omicron variant (Omicron variant group) admitted to the Fifth Affiliated Hospital of Sun Yat-sen University from January 13 to March 20, 2022 were included, and 88 patients with non SARS-CoV-2 Omicron variant (non-Omicron variant group) from January 17 to February 17, 2020 were included. A retrospective study was conducted to compare myocardial damage, abnormal electrocardiogram and clinical characteristics between the two groups. Results The mean age of patients in Omicron variant group was smaller than that in non-Omicron variant group [(36. 6±15. 6) years vs. (49. 8±14. 3) years, P<0. 01], and the proportion of patients with body temperature, systolic blood pressure and fever at admission was lower than that of non-Omicron variant group (P<0. 05). The neutrophil / lymphocyte ratio [(2. 93 (3. 03, 5. 81) vs. 7. 06 (2. 32, 11. 27), P<0. 001], interleukin-2 (IL-2) and interleukin-6 (IL-6) levels in Omicron variant group were significantly lower than those in non-Omicron variant group (P<0. 01). Cardiac troponin I (cTnI) was negative in Omicron variant group, and the concentrations of cTnI, creatine kinase-MB isozyme (CK-MB) and N-terminal pro-brain natriuretic peptide (NT-proB-NP) and the proportion of patients with elevated levels were significantly lower than those of non-Omicron variant group (P<0. 01). The incidence of abnormal electrocardiogram in Omicron variant group was also significantly lower than that in non-Omicron variant group (25. 0% vs. 42. 0%, P = 0. 001), sinus tachycardia, atrial premature beats and T wave changes were the main symptoms. Atrial premature beats, T wave changes, ST segment depression and bundle branch block were the main symptoms in non-Omicron variant group. Conclusions The patients infected with SARS-CoV-2 Omicron variant in Zhuhai may not have obvious myocardial damage because most of the patients have been vaccinated with COVID-19 vaccine. The incidence of abnormal electrocardiogram is also significantly lower than that of non-Omicron variant group, mainly sinus tachycardia, atrial premature beats and T wave changes. © 2022, Editorial Office of Chinese Journal of Arteriosclerosis. All rights reserved.

Analysis of the Solution of a Model of SARS-CoV-2 Variants and Its Approximation Using Two-Step Lagrange Polynomial and Euler Techniques

In this paper, a vaccination model for SARS-CoV-2 variants is proposed and is studied using fractional differential operators involving a non-singular kernel. It is worth mentioning that variability in transmission rates occurs because of the particular population that is vaccinated, and hence, the asymptomatic infected classes are classified on the basis of their vaccination history. Using the Banach contraction principle and the Arzela–Ascoli theorem, existence and uniqueness results for the proposed model are presented. Two different numerical approaches, the fractional Euler and Lagrange polynomial methods, are employed to approximate the model's solution. The model is then fitted to data associated with COVID-19 deaths in Pakistan between 1 January 2022 and 10 April 2022. It is concluded that our model is much aligned with the data when the order of the fractional derivative (Formula presented.). The two different approaches are then compared with different step sizes. It is observed that they behave alike for small step sizes and exhibit different behaviour for larger step sizes. Based on the numerical assessment of the model presented herein, the impact of vaccination and the fractional order are highlighted. It is also noted that vaccination could remarkably decrease the spikes of different emerging variants of SARS-CoV-2 within the population. © 2023 by the authors.

Survival Analysis of Delta versus Omicron Variants in COVID-19 Intensive Care Unit (ICU)

Objective: COVID-19 has presented numerous epidemiological and clinical pictures from its beginning and much effort has been paid to detect the behavior of disease and its new types. Therefore, in this study, we aimed to compare the in-hospital survival time of Delta and Omicron variant patients admitted to the intensive care unit. Methods: This was a secondary data analysis of the QCOVICU data registry of 200 COVID-19 patients admitted to the ICU of Shahid Beheshti-Amir Al-Momenin Hospital of Qom City, in 2021. Likewise, time to event data, demographics, and baseline laboratory data was collected. Time of transfer to ICU, survivals, and possible predictors of hazards of death was compared within the variants of Omicron and delta. Results: Two hundred patients (62.98±19.94 years old, 94 females/106 males;100 Delta and 100 Omicron variant) participated in this study. Fifty percent of the population had died. Cross-tabulation showed comparable death rates among variants of delta and omicron (50.5% vs. 51%;p=0.999). There was a statistically significant higher time to ICU admission in Delta variant victims than in Omicron variant victims. The mean survival time of delta variant patients was 21.52 days (95% CI: 17.96 – 25.09) which was statistically higher than the mean survival of omicron patients (17.15 days, 95% CI: 13.65-20.64, p=0.018). The mean survival time of delta variant patients was statistically higher than omicron patients (21.52 vs. 17.15 days, p=0.018). Gender, age (years), and lymphocyte count were significant predictors of mortality based on the Cox regression analysis (P>0.05). There was a 5.9 times higher risk of mortality in females compared with males' gender after adjusting for other variables and a 5.6% increase in death risk with a 1-year increase in age, and a 31.8% decrease in death risk with a 1% lymphocyte percentage increase. Conclusion: Critically patients with Delta variant are getting ICU admitted later and withstand more days at ICU than Omicron patients. It seems that Omicron variant causes sudden deterioration of the patient's condition. © 2023 by SPC (Sami Publishing Company).

Management and standardization of hemodialysis centers in lockdown areas under the epidemic of coronavirus disease 2019.

Maintenance hemodialysis patients need to return to hospital 3 times a week for routine hemodialysis treatment. In the case of coronavirus disease 2019 (COVID-19) and regional lockdown, a set of management systems and standardizations has been established in our hemodialysis center, including forward movement of the critical nodes of treatment, specialists pooling program for hemodialysis technology, and dynamic bubble personnel management, to implement dynamic prevention and control strategies, precise management of inpatient wards and closed-loop management of outbreaks. While improving the management of our own hemodialysis center, it is recommended to strengthen multi-center collaboration to build a municipal grid management system for hemodialysis and explore different dialysis strategies for end-stage renal disease to meet the treatment needs and safety management of maintenance hemodialysis patients in lockdown areas under the epidemic.Copyright © 2022, Second Military Medical University Press. All rights reserved.

Integration of neural network and distance relay to improve the fault localization on transmission lines

Power transmission lines are integral and very important components of power systems. Because of the length of these lines and the complexity of the power grids, the lines may encounter various incidents such as lightning strike, shortage, and breakage. When an incident or a fault occurs, a fast process of identification, localization, and isolation of the fault is desired. An accurate fault localization would have a great impact in reducing the restoration time of the system. One of the most popular solutions for fault detection and localization is the distance relays using the impedance-based algorithms. However, these relays are still not perfect with nonzero errors of the fault locations. This paper will present a new approach using the neural networks in addition to a distance relays to correct the fault location estimation of the relay. The solution will be based only on the voltage and current signals measured at the beginning of the lines. The training samples' signals of the transient states on the lines are generated using ATP/EMTP, and then regenerated into the relay tester Omicron CMC-356 to test with the real Siemens 7SA522 relay to improve its fault location results. The numerical results will show that the solution had helped to reduce the average fault location error from 0.92% to 0.42% for 4 types of shortage faults on the lines. [ FROM AUTHOR] Copyright of Turkish Journal of Electrical Engineering & Computer Sciences is the property of Scientific and Technical Research Council of Turkey and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Population-Based Model of the Fraction of Incidental COVID-19 Hospitalizations during the Omicron BA.1 Wave in the United States

1. Background: Some reports have suggested that as many as one-half of all hospital inpatients identified as COVID-19-positive during the Omicron BA.1 variant-driven wave were incidental cases admitted primarily for reasons other than their viral infections. To date, however, there are no prospective longitudinal studies of a representative panel of hospitals based on pre-established criteria for determining whether a patient was, in fact, admitted as a result of the disease. 2. Materials and Methods: To fill this gap, we developed a formula to estimate the fraction of incidental COVID-19 hospitalizations that relies on measurable, population-based parameters. We applied our approach to a longitudinal panel of 164 counties throughout the United States, covering a 4-week interval ending in the first week of January 2022. 3. Results: Within this panel, we estimated that COVID-19 incidence was rising exponentially at a rate of 9.34% per day (95% CI, 8.93–9.87). Assuming that only one-quarter of all Omicron BA.1 infections had been reported by public authorities, we further estimated the aggregate prevalence of active SARS-CoV-2 infection during the first week of January to be 3.45%. During the same week, among 250 high-COVID-volume hospitals within our 164-county panel, an estimated one in four inpatients was COVID-positive. Based upon these estimates, we computed that 10.6% of such COVID-19-positive hospitalized patients were incidental infections. Across individual counties, the median fraction of incidental COVID-19 hospitalizations was 9.5%, with an interquartile range of 6.7 to 12.7%. 4. Conclusion: Incidental COVID-19 infections appear to have been a nontrivial fraction of all COVID-19-positive hospitalized patients during the Omicron BA.1 wave. In the aggregate, however, the burden of patients admitted for complications of their viral infections was far greater. [ FROM AUTHOR] Copyright of COVID is the property of MDPI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Clinical significance of serum interleukin 6 in elderly patients infected with severe acute respiratory syndrome coronavirus 2 omicron variant and its correlation with underlying diseases.

Objective To investigate the clinical significance of serum interleukin 6 (IL-6) in elderly patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant and its correlation with underlying diseases. Methods A total of 22 elderly patients (80 years old) infected with omicron variant, who were admitted to Department of Infectious Diseases, The First Affiliated Hospital of Naval Medical University (Second Military Medical University) from Apr. to Jun. 2022 and tested positive for SARS-CoV-2 RNA, were included. The level of serum IL-6 was measured by flow cytometry, and the level of serum C reactive protein (CRP) was measured by immunonephelometry. Patients were divided into pneumonia group (16 cases) and non-pneumonia group (6 cases) according to the imaging examination results, and were divided into severe group (severe and critical type, 5 cases) and non-severe group (mild and normal type, 17 cases) according to the condition. Binary logistic regression model and receiver operating characteristic (ROC) curve were used to analyze the correlation between serum IL-6 and CRP levels and the severity of the disease and whether it would progress to pneumonia. Meanwhile, the relationships between underlying diseases and serum IL-6 level were explored. Results Among the 22 patients, 6 were mild, 11 were normal, 3 were severe, and 2 were critical. The baseline serum IL-6 level in the pneumonia group was significantly higher than that in the non-pneumonia group (20.16+/-12.36pg/mL vs 5.42+/-1.57 pg/mL, P=0.009), and there was no significant difference in baseline serum CRP level between the 2 groups (P0.05). There were no significant differences in baseline serum IL-6 or CRP levels between the severe group and the non-severe group (both P0.05). Logistic regression analysis showed that the baseline serum IL-6 and CRP might be related to pneumonia after infection with omicron variant (odds ratio OR=2.407, 95% confidence interval CI0.915-6.328;OR=1.030, 95% CI 0.952-1.114). ROC curve analysis showed that the area under curve values of serum IL-6 and CRP in predicting the progression to pneumonia were 0.969 (95% CI 0.900-1.000) and 0.656 (95% CI 0.380-0.932), respectively, with statistical significance (Z=2.154, P=0.030). There were no significant differences in the baseline serum IL-6 level or proportions of severe patients or pneumonia patients among patients with or without hypertension, diabetes mellitus, coronary heart disease, chronic kidney disease or chronic obstructive pulmonary disease (all P0.05). The baseline serum IL-6 levels of the omicron variant infected elderly patients with 1, 2, and 3 or more underlying diseases were 12.50 (9.15, 21.75), 23.55 (9.63, 50.10), and 10.90 (5.20, 18.88) pg/mL, respectively, with no statistical significance (P0.05). Conclusion For omicron variant infected patients, serum IL-6 level is significantly increased in patients with pneumonia manifestations and is correlated with disease progression. Serum IL-6 level is of great guiding significance to judge disease progression and evaluate efficacy and prognosis of elderly coronavirus disease 2019 patients.Copyright © 2022, Second Military Medical University Press. All rights reserved.

The impact of vaccination on the dynamics of the Omicron variant of SARS-CoV-2

In the context of vaccination, we develop a novel mathematical model to examine the Omicron type of coronavirus illness. The system's mathematical analysis based on its equilibrium points shall be obtained. The threshold quantity is used to investigate the system's local and global asymptotical analysis. The Omicron vaccination model shown to be stable locally asymptotically if R 0 v < 1 . The system is globally asymptotically stable at the disease-free equilibrium for a special case when η = 1 if R 0 v < 1 . We estimate the model parameters based on the observed data and show that the threshold is R 0 ≈ 2.4894 in the absence of vaccination. The model has the phenomenon of backward bifurcation under certain conditions. Herd immunity analysis is obtained and it turns out that the herd immunity threshold for the South African population is 74%. The impact of vaccination on disease dynamics is also shown and discussed. Further, we have given some graphical results showing the community's disease reduction. [ FROM AUTHOR] Copyright of Waves in Random & Complex Media is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Mental health status of military healthcare workers in shelter hospitals in Shanghai during the epidemic caused by severe acute respiratory syndrome coronavirus 2 omicron variant and its influencing factors.

Objective To investigate the mental health status of military healthcare workers in shelter hospitals in Shanghai during the epidemic caused by severe acute respiratory syndrome coronavirus 2 omicron variant and its influencing factors. Methods A total of 540 military healthcare workers in shelter hospitals in Shanghai were investigated with patient health questionnaire-9 (PHQ-9), generalized anxiety disorder-7 (GAD-7) and Athens insomnia scale (AIS) to explore their mental health status, and logistic regression was used to analyze the influencing factors. Results A total of 536 valid questionnaires were collected, with an effective rate of 99.3% (536/540). The incidence of depression, anxiety and insomnia among military healthcare workers in shelter hospitals in Shanghai was 45.5% (244/536), 26.1% (140/536) and 59.5% (319/536), respectively. Logistic regression analysis showed that whether people resided in Shanghai, the proportion of negative information in daily browsing information and diet status in shelter hospitals were the influencing factors of depression, anxiety and insomnia (all P<0.05);age and confidence in the future of Shanghai were the influencing factors of depression and insomnia (all P<0.05);and the time spent daily on epidemic-related information was an influencing factor of insomnia (P=0.021). Conclusion The incidence of depressive, anxiety and insomnia among military healthcare workers in shelter hospitals in Shanghai is high during the epidemic caused by severe acute respiratory syndrome coronavirus 2 omicron variant. Psychological consequences of the epidemic should be monitored regularly and continuously to promote the mental health of military healthcare workers.Copyright © 2022, Second Military Medical University Press. All rights reserved.

[Clinical features of 23 neonates infected with Omicron variant of severe acute respiratory syndrome coronavirus 2]. / æ–°ç”Ÿå„¿æ–°åž‹å† çŠ¶ç— æ¯’Omicronå˜å¼‚æ ªæ„ŸæŸ“23例临床分析.

OBJECTIVES: To summarize the clinical features of neonates infected with Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: The medical data of 23 neonates with Omicron variant of SARS-CoV-2 infection admitted to the City North Campus of Urumqi First People's Hospital from October to December 2022 were retrospectively reviewed. RESULTS: All 23 infants had a history of exposure to confirmed caregivers with SARS-CoV-2 infection after birth, and none of them was vertically transmitted. Clinical classification: 5 cases of asymptomatic infection, 18 cases of mild infection, and no cases of moderate, severe, or critically ill. The first symptoms were fever in 13 cases, cough in 3 cases, nasal congestion in 1 case, and diarrhea in 1 case. Blood white blood cell counts decreased in 2 cases, and C-reactive protein increased in 1 case. Seven infants underwent chest X-ray examination due to cough or shortness of breath, and one of which showed focal exudative changes, while the rest showed no abnormal changes. All infants were discharged after symptomatic treatment and the median hospital stay was 6 days. The duration of nucleic acid positivity of SARS-CoV-2 was negatively correlated with N gene Ct values and ORF1ab gene Ct values (rs=-0.719 and -0.699, respectively; P<0.05). One month after discharge, all infants had no symptoms or signs of nucleic acid re-positivity. CONCLUSIONS: The clinical manifestations are usually mild or asymptomatic in neonates infected with SARS-CoV-2 Omicron variant. The lower the Ct values of the N and ORF1ab genes of SARS-CoV-2, the longer the duration of nucleic acid positivity. Neonates infected with SARS-CoV-2 Omicron variant can have a good prognosis after symptomatic treatment.

Identification of key mutations responsible for the enhancement of receptor-binding affinity and immune escape of SARS-CoV-2 Omicron variant.

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has raised concerns worldwide due to its enhanced transmissibility and immune escapability. The first dominant Omicron BA.1 subvariant harbors more than 30 mutations in the spike protein from the prototype virus, of which 15 mutations are located at the receptor binding domain (RBD). These mutations in the RBD region attracted significant attention, which potentially enhance the binding of the receptor human angiotensin-converting enzyme 2 (hACE2) and decrease the potency of neutralizing antibodies/nanobodies. This study applied the molecular dynamics simulations combined with the molecular mechanics-generalized Born surface area (MMGBSA) method, to investigate the molecular mechanism behind the impact of the mutations acquired by Omicron on the binding affinity between RBD and hACE2. Our results indicate that five key mutations, i.e., N440K, T478K, E484A, Q493R, and G496S, contributed significantly to the enhancement of the binding affinity by increasing the electrostatic interactions of the RBD-hACE2 complex. Moreover, fourteen neutralizing antibodies/nanobodies complexed with RBD were used to explore the effects of the mutations in Omicron RBD on their binding affinities. The calculation results indicate that the key mutations E484A and Y505H reduce the binding affinities to RBD for most of the studied neutralizing antibodies/nanobodies, mainly attributed to the elimination of the original favorable gas-phase electrostatic and hydrophobic interactions between them, respectively. Our results provide valuable information for developing effective vaccines and antibody/nanobody drugs.

Impact of Severe Acute Respiratory Syndrome Coronavirus 2 Variants on Inpatient Clinical Outcome.

BACKGROUND: Prior observation has shown differences in COVID-19 hospitalization risk between SARS-CoV-2 variants, but limited information describes hospitalization outcomes. METHODS: Inpatients with COVID-19 at 5 hospitals in the eastern United States were included if they had hypoxia, tachypnea, tachycardia, or fever, and SARS-CoV-2 variant data, determined from whole-genome sequencing or local surveillance inference. Analyses were stratified by history of SARS-CoV-2 vaccination or infection. The average effect of SARS-CoV-2 variant on 28-day risk of severe disease, defined by advanced respiratory support needs, or death was evaluated using models weighted on propensity scores derived from baseline clinical features. RESULTS: Severe disease or death within 28 days occurred for 977 (29%) of 3369 unvaccinated patients and 269 (22%) of 1230 patients with history of vaccination or prior SARS-CoV-2 infection. Among unvaccinated patients, the relative risk of severe disease or death for Delta variant compared with ancestral lineages was 1.30 (95% confidence interval [CI]: 1.11-1.49). Compared with Delta, the risk for Omicron patients was .72 (95% CI: .59-.88) and compared with ancestral lineages was .94 (.78-1.1). Among Omicron and Delta infections, patients with history of vaccination or prior SARS-CoV-2 infection had half the risk of severe disease or death (adjusted hazard ratio: .40; 95% CI: .30-.54), but no significant outcome difference by variant. CONCLUSIONS: Although risk of severe disease or death for unvaccinated inpatients with Omicron was lower than with Delta, it was similar to ancestral lineages. Severe outcomes were less common in vaccinated inpatients, with no difference between Delta and Omicron infections.

SARS-CoV-2 Vaccine Breakthrough Infections of Omicron and Delta Variants in Healthcare Workers.

Understanding SARS-CoV-2 breakthrough infections in vaccinated healthcare workers is of key importance in mitigating the effects of the COVID-19 pandemic in healthcare facilities. An observational prospective cohort study was conducted in vaccinated employees with acute SARS-CoV-2 infection between October 2021 and February 2022. Serological and molecular testing was performed to determine SARS-CoV-2 viral load, lineage, antibody levels, and neutralizing antibody titers. A total of 571 (9.7%) employees experienced SARS-CoV-2 breakthrough infections during the enrolment period, of which 81 were included. The majority (n = 79, 97.5%) were symptomatic and most (n = 75, 92.6%) showed Ct values < 30 in RT-PCR assays. Twenty-four (30%) remained PCR-positive for > 15 days. Neutralizing antibody titers were strongest for the wildtype, intermediate for Delta, and lowest for Omicron variants. Omicron infections occurred at higher anti-RBD-IgG serum levels (p = 0.00001) and showed a trend for higher viral loads (p = 0.14, median Ct difference 4.3, 95% CI [-2.5-10.5]). For both variants, viral loads were significantly higher in participants with lower anti-RBD-IgG serum levels (p = 0.02). In conclusion, while the clinical course of infection with both the Omicron and Delta variants was predominantly mild to moderate in our study population, waning immune response over time and prolonged viral shedding were observed.

Comparison between original SARS-CoV-2 strain and omicron variant on thin-section chest CT imaging of COVID-19 pneumonia.

OBJECTIVES: We investigated different computed tomography (CT) features between Omicron-variant and original-strain SARS-CoV­2 pneumonia to facilitate the clinical management. MATERIALS AND METHODS: Medical records were retrospectively reviewed to select patients with original-strain SARS-CoV­2 pneumonia from February 22 to April 22, 2020, or Omicron-variant SARS-CoV­2 pneumonia from March 26 to May 31, 2022. Data on the demographics, comorbidities, symptoms, clinical types, and CT features were compared between the two groups. RESULTS: There were 62 and 78 patients with original-strain or Omicron-variant SARS-CoV­2 pneumonia, respectively. There were no differences between the two groups in terms of age, sex, clinical types, symptoms, and comorbidities. The main CT features differed between the two groups (p = 0.003). There were 37 (59.7%) and 20 (25.6%) patients with ground-glass opacities (GGO) in the original-strain and Omicron-variant pneumonia, respectively. A consolidation pattern was more frequently observed in the Omicron-variant than original-strain pneumonia (62.8% vs. 24.2%). There was no difference in crazy-paving pattern between the original-strain and Omicron-variant pneumonia (16.1% vs. 11.6%). Pleural effusion was observed more often in Omicron-variant pneumonia, while subpleural lesions were more common in the original-strain pneumonia. The CT score in the Omicron-variant group was higher than that in the original-strain group for critical-type (17.00, 16.00-18.00 vs. 16.00, 14.00-17.00, p = 0.031) and for severe-type (13.00, 12.00-14.00 vs 12.00, 10.75-13.00, p = 0.027) pneumonia. CONCLUSION: The main CT finding of the Omicron-variant SARS-CoV­2 pneumonia included consolidations and pleural effusion. By contrast, CT findings of original-strain SARS-CoV­2 pneumonia showed frequent GGO and subpleural lesions, but without pleural effusion. The CT scores were also higher in the critical and severe types of Omicron-variant than original-strain pneumonia.

Re-examine the transfusion transmitted risk of SARS-CoV-2 virus during a major COVID-19 outbreak in 2022.

INTRODUCTION: Although no case of COVID-19 transmission through transfusion has been reported, blood transfusion service (BTS) continues to implement pre-donation and post-donation measures to minimise the risk. In year 2022, when local healthcare system was badly impacted by a major outbreak, it opened an opportunity to re-examine the viraemia risk in these asymptomatic donors. MATERIALS AND METHODS: Records were retrieved from blood donors who reported COVID-19 after donation and follow-up was also made for recipients who received their blood. Blood samples at donation were tested for SARS-CoV-2 viraemia by single-tube nested real-time RT-PCR assay designed to detect most SARS-CoV-2 variants including the prevailing delta and omicron variants. RESULTS: From 1 January to 15 August 2022, the city with 7.4 M inhabitants recorded 1 187 844 COVID-19 positive cases and 125 936 successful blood donations were received. 781 donors reported to the BTS after donation with 701 being COVID-19 related (including close contact and symptoms respiratory tract infection). 525 COVID-19 were positive at the time of call back or follow-up. Of the 701 donations, they were processed into 1480 components with 1073 discarded upon donors' call back. For remaining 407 components, no recipient was found to have adverse event or COVID-19 positive. 510 samples from the above 525 COVID-19 positive donors were available and all tested negative for SARS-CoV-2 RNA. DISCUSSION: With the negative SARS-CoV-2 RNA in blood donation samples and follow up data in transfusion recipients, the risk of transfusion transmitted COVID-19 appears negligible. However, current measures remains important in securing blood safety with ongoing surveillance of their effectiveness.

Prevalence and associating factors of long COVID in pediatric patients during the Delta and the Omicron variants.

Introduction: The number of pediatric COVID-19 infections is increasing; however, the data on long COVID conditions in children is still limited. Our study aimed to find the prevalence of long COVID in children during the Delta and Omicron waves, as well as associated factors. Methods: A single-center prospective cohort study was conducted. We included 802 RT-PCR-confirmed COVID-19 pediatric patients in the Delta and Omicron periods. Long COVID was defined as having symptoms for ≥3 months after infection. Parents and/or patients were interviewed by phone. Multivariable logistic regression was performed to find associated factors with long COVID. Results: The overall prevalence of long COVID was 30.2%. The Delta period had more prevalence than the Omicron (36.3% vs. 23.9%). Common symptoms for patients 0-3 years' old were loss of appetite, rhinorrhea, and nasal congestion. Conversely, patients 3-18 years' old had hair loss, dyspnea on exertion, rhinorrhea, and nasal congestion. However, there was no significant negative impact on daily life. Most symptoms improved after a 6-month follow-up. Factors associated with long COVID-19 conditions were infection during the Omicron period (adjusted OR: 0.54; 95% CI: 0.39-0.74, P < 0.001), fever (adjusted OR: 1.49, 95% CI: 1.01-2.20, P = 0.04) and rhinorrhea (adjusted OR: 1.47, 95% CI: 1.06-2.02, P = 0.02). Conclusion: Infection during the Omicron wave has a lower prevalence of long COVID. The prognosis is often favorable, and most symptoms gradually become less. However, pediatricians may schedule appointments to surveil long COVID in children with fever or rhinorrhea as an initial symptom.

A Comparison of Clinical Presentations in Coronavirus Disease 2019 Caused by Different Omicron variants in Japan: A Retrospective Study.

Objective We evaluated the clinical differences in coronavirus disease 2019 (COVID-19) patients between the sixth wave with the Omicron BA.1/BA.2 dominant variant (from January to April 2022) and seventh wave with the Omicron BA.5 dominant variant (from July to August 2022). Methods This retrospective, single-center, observational study included COVID-19 patients admitted to our institution in the sixth wave (sixth-wave group) and the seventh wave (seventh-wave group). Inter-group comparisons of clinical presentations, the prognosis, and proportion of nosocomial infections were performed. Results A total of 190 patients were included (93 and 97 patients in the sixth- and seventh-wave groups, respectively). While there were no significant differences in severity, significantly more patients developed pneumonia caused by COVID-19 in the sixth-wave group than in the seventh-wave group. Although there was no marked difference in in-hospital deaths, more patients died from COVID-19 in the sixth-wave group than in the seventh-wave group. There were significantly more COVID-19 inpatients with nosocomial infections in the seventh-wave group than in the sixth-wave group. Pneumonia from COVID-19 was significantly more severe in the sixth-wave group than in the seventh-wave group. Conclusions COVID-19 patients in the seventh wave are at a lower risk of pneumonia than those in the sixth wave. However, even in the seventh wave, patients with underlying diseases have a risk of death because of the exacerbation of underlying diseases triggered by COVID-19.