Abstract
Recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants may pose a threat to immunity. A systematic landscape of neutralizing antibodies against emerging ...variants is needed. We systematically searched for studies that evaluated neutralizing antibody titers induced by previous infection or vaccination against SARS-CoV-2 variants and collected individual data. We identified 106 studies meeting the eligibility criteria. Lineage B.1.351 (beta), P.1 (gamma) and B.1.617.2 (delta) significantly escaped natural infection–mediated neutralization, with an average of 4.1-fold (95% confidence interval CI: 3.6–4.7-fold), 1.8-fold (1.4–2.4-fold), and 3.2-fold (2.4–4.1-fold) reduction in live virus neutralization assay, while neutralizing titers against B.1.1.7 (alpha) decreased slightly (1.4-fold 95% CI: 1.2–1.6-fold). Serum from vaccinees also led to significant reductions in neutralization of B.1.351 across different platforms, with an average of 7.1-fold (95% CI: 5.5–9.0-fold) for nonreplicating vector platform, 4.1-fold (3.7–4.4-fold) for messenger RNA platform, and 2.5-fold (1.7–2.9-fold) for protein subunit platform. Neutralizing antibody levels induced by messenger RNA vaccines against SARS-CoV-2 variants were similar to, or higher, than that derived from naturally infected individuals.
Antibody response established by infection or vaccination might enable effectively neutralize B.1.1.7 (alpha), but with large reductions in neutralizing titers against B.1.351 (beta), B.1.617.2 (delta) and P.1 (gamma). Standardized protocols for neutralization assays and updated prevention and treatment are needed.
Genomic surveillance has shaped our understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. We performed a global landscape analysis on SARS-CoV-2 genomic surveillance ...and genomic data using a collection of country-specific data. Here, we characterize increasing circulation of the Alpha variant in early 2021, subsequently replaced by the Delta variant around May 2021. SARS-CoV-2 genomic surveillance and sequencing availability varied markedly across countries, with 45 countries performing a high level of routine genomic surveillance and 96 countries with a high availability of SARS-CoV-2 sequencing. We also observed a marked heterogeneity of sequencing percentage, sequencing technologies, turnaround time and completeness of released metadata across regions and income groups. A total of 37% of countries with explicit reporting on variants shared less than half of their sequences of variants of concern (VOCs) in public repositories. Our findings indicate an urgent need to increase timely and full sharing of sequences, the standardization of metadata files and support for countries with limited sequencing and bioinformatics capacity.
A rapidly increasing number of serological surveys for antibodies to SARS-CoV-2 have been reported worldwide. We aimed to synthesise, combine, and assess this large corpus of data.
In this systematic ...review and meta-analysis, we searched PubMed, Embase, Web of Science, and five preprint servers for articles published in English between Dec 1, 2019, and Dec 22, 2020. Studies evaluating SARS-CoV-2 seroprevalence in humans after the first identified case in the area were included. Studies that only reported serological responses among patients with COVID-19, those using known infection status samples, or any animal experiments were all excluded. All data used for analysis were extracted from included papers. Study quality was assessed using a standardised scale. We estimated age-specific, sex-specific, and race-specific seroprevalence by WHO regions and subpopulations with different levels of exposures, and the ratio of serology-identified infections to virologically confirmed cases. This study is registered with PROSPERO, CRD42020198253.
16 506 studies were identified in the initial search, 2523 were assessed for eligibility after removal of duplicates and inappropriate titles and abstracts, and 404 serological studies (representing tests in 5 168 360 individuals) were included in the meta-analysis. In the 82 studies of higher quality, close contacts (18·0%, 95% CI 15·7–20·3) and high-risk health-care workers (17·1%, 9·9–24·4) had higher seroprevalence than did low-risk health-care workers (4·2%, 1·5–6·9) and the general population (8·0%, 6·8–9·2). The heterogeneity between included studies was high, with an overall I2 of 99·9% (p<0·0001). Seroprevalence varied greatly across WHO regions, with the lowest seroprevalence of general populations in the Western Pacific region (1·7%, 95% CI 0·0–5·0). The pooled infection-to-case ratio was similar between the region of the Americas (6·9, 95% CI 2·7–17·3) and the European region (8·4, 6·5–10·7), but higher in India (56·5, 28·5–112·0), the only country in the South-East Asia region with data.
Antibody-mediated herd immunity is far from being reached in most settings. Estimates of the ratio of serologically detected infections per virologically confirmed cases across WHO regions can help provide insights into the true proportion of the population infected from routine confirmation data.
National Science Fund for Distinguished Young Scholars, Key Emergency Project of Shanghai Science and Technology Committee, Program of Shanghai Academic/Technology Research Leader, National Science and Technology Major project of China, the US National Institutes of Health.
For the Chinese translation of the abstract see Supplementary Materials section.
This paper presents an application of ultrahigh-performance liquid chromatography and electrospray ionization quadrupole Orbitrap high-resolution mass spectrometry (UHPLC/ESI Q-Orbitrap) for ...determination of 166 pesticide residues in fruits and vegetables. Pesticides were extracted from the samples using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure. UHPLC/ESI Q-Orbitrap MS (i.e., full MS scan) acquired full MS data for quantification, and UHPLC/ESI Q-Orbitrap dd-MS2 (i.e., data-dependent scan) obtained product-ion spectra for confirmation. UHPLC/ESI Q-Orbitrap MS quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or chemical analogues as internal standards. The method performance characteristics that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested experimental design. For the matrices studied, about 90.3–91.5% of the pesticides had recoveries between 81 and 110%, 92.1–97.6% had intermediate precision ≤20%, and 89.7–95.2% had measurement uncertainty ≤40%. Confirmation was based on mass accuracy ≤5 ppm and LC retention time tolerance within ±2.5%. Overall, the UHPLC/ESI Q-Orbitrap has demonstrated great performance for quantification and confirmation of pesticide residues in fresh fruits and vegetables.
Being one of the "mega trends" that has significantly impacted the tourism system, the role and use of social media in travelers' decision making and in tourism operations and management have been ...widely discussed in tourism and hospitality research. This study reviews and analyzes all extant social media-related research articles published in academic journals during 2007 to 2011, mainly in tourism and hospitality fields. Based on a content analysis on the analyzed articles from both the consumers' and the suppliers' perspectives, this article found that consumer-centric studies generally focused on the use and impact of social media in the research phase of the travelers' travel planning process. Supplier-related studies have concentrated closely on promotion, management, and research functions, but few discussed product distribution. Research findings thoroughly demonstrate the strategic importance of social media for tourism competitiveness. This study also contributes to the academia and industry by identifying some research voids in extant research and providing an agenda for future research.
Up to 90% of people with CF (pwCF) will have some form of hepatobiliary involvement. This manuscript aims to explore the different endovascular, endoscopic, radiological and surgical procedures ...available to diagnose and manage the most severe form of CF hepatobiliary involvement (CFHBI) known as advanced cystic fibrosis liver disease (aCFLD), seen in 10% of pwCF. These procedures and interventions include liver biopsy, hepatic venous pressure gradient measurement, gastrostomy tube placement to optimize nutrition, paracentesis, endoscopic variceal control of bleeding and portosystemic shunting before liver transplantation. By utilizing advanced diagnostic or surgical techniques, healthcare professionals of pwCF can more effectively manage patients with CFHBI and aCFLD and potentially improve patient outcomes.
Aim
The growth of the ageing population has been rapid. However, this ageing population is not homogeneous; individuals have different levels of functionality and psychosocial status, and some are ...members of at‐risk or high‐risk groups. As such, studies on the functional, psychological, and environmental factors of falls among community‐dwelling older adults are imperative. By investigating the effect of life satisfaction, as well as environmental and functional factors, on falls among community‐dwelling older adults in Hong Kong, this study aims to address this concern.
Methods
The study recruited 249 participants. Both self‐reported questionnaires and home safety assessments were administrated.
Results
Logistic regression analysis showed that life satisfaction and instrumental activities of daily living were significant predictors of falls. Significant differences between fallers and non‐fallers were found in functional and psychological areas. The presence of home hazards was low and not associated with falls in this population. However, this variable was negatively associated with life satisfaction and predicted by one of its domains, satisfaction of possession.
Conclusion
These results can help health‐care and social service providers to identify the needs and types of support required for effective fall prevention and to better tailor and target community intervention for older adults.
Hepatitis B and C Mysore, Krupa R; Leung, Daniel H
Clinics in liver disease,
11/2018, Letnik:
22, Številka:
4
Journal Article
Recenzirano
Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections represent a major global public health and economic burden, with an estimated 257 million and 71 million people, respectively, having ...chronic infection worldwide. The natural history of HBV and HCV in children depends on age at time of infection, mode of acquisition, ethnicity, and genotype. Most children infected perinatally or vertically remain asymptomatic but are at uniquely higher risk of developing chronic viral hepatitis, progressing to liver cirrhosis and hepatocellular carcinoma (HCC), hence classifying HBV and HCV as oncoviruses. This article discusses the epidemiology, virology, immunobiology, prevention, clinical manifestations, evaluation, and the advances in treatment of hepatitis B and C in children.
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