scholarly journals Unveiling the omicron B.1.1. 529: The variant of concern that is rattling the globe

2022 ◽  
Vol 13 (1) ◽  
pp. 166-168
Author(s):  
Ruby Dhar ◽  
Joyeeta Talukdar ◽  
Arnab Nayek ◽  
Swati Ajmeriya ◽  
Arun Kumar ◽  
...  

Most viruses–including SARS-CoV-2, seem to have evolved over time. The lack of stringent proofreading mechanisms makes viral DNA/RNA replication error-prone. When a virus replicates, it sometimes changes a little bit, which is called mutations. Any virus with one or more new mutations can be referred to as a “variant” of the original virus. The last 2 years have witnessed the emergence of a large number of variants. Since the pandemic’s beginning, the SARS-CoV-2 coronavirus has mutated extensively, resulting in the emergence of different variants of the virus. One of these is the delta variant (arising from Pango lineage B.1.617.2) that took the word in a storm this year (February-July). The current a variant of concern is the B.1.1.529 (Omicron) variant reported first from South Africa on November 24, 2021. In recent weeks, infections have been widely reported, along with the increased detection of the B.1.1.529 variant. We reviewed the emergence of the new variant (B1.1.529) and its possible outcomes.

2021 ◽  
Author(s):  
Stefanie Weber ◽  
Christina M. Ramirez ◽  
Barbara Weiser ◽  
Harold Burger ◽  
Walter Doerfler

AbstractScientists and the public were alarmed at the first large viral variant of SARS-CoV2 reported in December 2020. We have followed the time course of emerging viral mutants and variants during the SARS-CoV-2 pandemic in ten countries on four continents. We examined complete SARS-CoV-2 nucleotide sequences in GISAID, (Global Initiative of Sharing All Influenza Data) with sampling dates extending until January 20, 2021. These sequences originated from ten different countries: United Kingdom, South Africa, Brazil, USA, India, Russia, France, Spain, Germany, and China. Among the novel mutations, some previously reported mutations waned and some of them increased in prevalence over time. VUI2012/01 (B.1.1.7) and 501Y.V2 (B.1.351), the so-called UK and South Africa variants, respectively, and two variants from Brazil, 484K.V2, now called P.1 and P.2, increased in prevalence. Despite lockdowns, worldwide active replication in genetically and socio-economically diverse populations facilitated selection of new mutations. The data on mutant and variant SARS-CoV-2 strains provided here comprise a global resource for easy access to the myriad mutations and variants detected to date globally. Rapidly evolving new variant and mutant strains might give rise to escape variants, capable of limiting the efficacy of vaccines, therapies, and diagnostic tests.Significance and New Aspects of Study – SynopsisWe examine the time course of emerging mutations in the SARS-CoV-2 genome that have rapidly been selected in the world’s populations through the beginning of 2021. A study of the prevalence of viral mutations in the GISAID database in ten different countries – United Kingdom, South Africa, Brazil, US, India, Russia, France, Spain, Germany, and China - revealed widespread mutations along the genome.We previously identified about 10 hotspot mutations in the SARS-CoV-2 genome that became prevalent in many of the countries studied1. Since the beginning of February, many new mutations arose in the ten countries (and worldwide). The preponderance of variants and mutations correlated with the increased spread of Covid-19.There was a temporal progression from about 10 predominant mutants shared by several countries up to the end of May 2020, followed by a consistent and rapid increase in the number of new mutations between June and December along with the emergence of variants of concern, first reported in December 2020.We examine the relative frequencies of mutations, along with variants of interest, in 10 countries up until January 20, 2021. Investigations on the pathogenic properties of individual SARS-CoV-2 mutations will be urgently needed to understand the kaleidoscopic patterns of worldwide Covid-19 outbreaks and symptoms. Monitoring the frequency and speed of mutant selection have direct relevance to diagnostic testing, vaccines and therapeutics.As an explanation for efficient viral mutagenesis, we hypothesize that the viral spike protein – as documented – facilitates viral entry via the cell’s ACE receptor2. This in turn interacts with the APOBEC polypeptide, an m-RNA editing function. The actually observed frequent C to U (T) transitions and other base exchanges are thus effected. Hence, as one of the earliest steps upon viral entry, active mutagenesis commences, since SARS-CoV-2 exploits one of the cell’s defenses against viral infections.


Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 633
Author(s):  
Yeong Jun Kim ◽  
Ui Soon Jang ◽  
Sandrine M. Soh ◽  
Joo-Youn Lee ◽  
Hye-Ra Lee

A new variant of SARS-CoV-2 B.1.351 lineage (first found in South Africa) has been raising global concern due to its harboring of multiple mutations in the spike that potentially increase transmissibility and yield resistance to neutralizing antibodies. We here tested infectivity and neutralization efficiency of SARS-CoV-2 spike pseudoviruses bearing particular mutations of the receptor-binding domain (RBD) derived either from the Wuhan strains (referred to as D614G or with other sites) or the B.1.351 lineage (referred to as N501Y, K417N, and E484K). The three different pseudoviruses B.1.351 lineage related significantly increased infectivity compared with other mutants that indicated Wuhan strains. Interestingly, K417N and E484K mutations dramatically enhanced cell–cell fusion than N501Y even though their infectivity were similar, suggesting that K417N and E484K mutations harboring SARS-CoV-2 variant might be more transmissible than N501Y mutation containing SARS-CoV-2 variant. We also investigated the efficacy of two different monoclonal antibodies, Casirivimab and Imdevimab that neutralized SARS-CoV-2, against several kinds of pseudoviruses which indicated Wuhan or B.1.351 lineage. Remarkably, Imdevimab effectively neutralized B.1.351 lineage pseudoviruses containing N501Y, K417N, and E484K mutations, while Casirivimab partially affected them. Overall, our results underscore the importance of B.1.351 lineage SARS-CoV-2 in the viral spread and its implication for antibody efficacy.


2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Janice Buckley ◽  
Kennedy Otwombe ◽  
Celeste Joyce ◽  
Given Leshabane ◽  
Lisa Galvin ◽  
...  

Author(s):  
Evangelia Georgia Kostaki ◽  
Ioulia Tseti ◽  
Sotirios Tsiodras ◽  
George N. Pavlakis ◽  
Petros P. Sfikakis ◽  
...  

Some emergent SARS-CoV-2 variants raise concerns due to their altered biological properties. For both B.1.1.7 and B.1351 variants, named as variants of concern (VOC), increased transmissibility was reported, whereas B.1.351 was more resistant to multiple monoclonal antibodies (mAbs), as well as convalescent and vaccination sera. To test this hypothesis, we examined the proportion of VOC over time across different geographic areas where the two VOC, B.1.1.7 and B.1.351, co-circulate. Our comparative analysis was based on the number of SARS-CoV-2 sequences on GISAID database. We report that B.1.1.7 dominates over B.1.351 in geographic areas where both variants co-circulate and the B.1.1.7 was the first variant introduced in the population. The only areas where B.1.351 was detected at higher proportion were South Africa and Mayotte in Africa, where this strain was associated with increased community transmission before the detection of B.1.1.7. The dominance of B.1.1.7 over B.1.351 could be important since B.1.351 was more resistant to certain mAbs, as well as heterologous convalescent and vaccination sera, thus suggesting that it may be transmitted more effectively in people with pre-existing immunity to other VOC. This scenario would lessen the effectiveness of vaccine and urge the need to update them with new strains.


2021 ◽  
Author(s):  
James A Ackland ◽  
Graeme J Ackland ◽  
David J Wallace

Objective: To track the statistical case fatality rate (CFR) in the second wave of the UK coronavirus outbreak, and to understand its variations over time. Design: Publicly available UK government data and clinical evidence on the time between first positive PCR test and death are used to determine the relationships between reported cases and deaths, according to age groups and across regions in England. Main Outcome Measures: Estimates of case fatality rates and their variations over time. Results: Throughout October and November 2020, deaths in England can be broadly understood in terms of CFRs which are approximately constant over time. The same CFRs prove a poor predictor of deaths when applied back to September, when prevalence of the virus was comparatively low, suggesting that the potential effect of false positive tests needs to be taken into account. Similarly, increasing CFRs are needed to match cases to deaths when projecting the model forwards into December. The growth of the S gene dropout VOC in December occurs too late to explain this increase in CFR alone, but at 33% increased mortality, it can explain the peak in deaths in January. On our analysis, if there were other factors responsible for the higher CFRs in December and January, 33% would be an upper bound for the higher mortality of the VOC. From the second half of January, the CFRs for older age groups show a marked decline. Since the fraction of the VOC has not decreased, this decline is likely to be the result of the rollout of vaccination. However, due to the rapidly decreasing nature of the raw cases data (likely due to a combination of vaccination and lockdown), any imprecisions in the time-to-death distribution are greatly exacerbated in this time period, rendering estimates of vaccination effect imprecise. Conclusions: The relationship between cases and deaths, even when controlling for age, is not static through the second wave of coronavirus in England. An apparently anomalous low case-fatality ratio in September can be accounted for by a modest 0.4% false-positive fraction. The large jump in CFR in December can be understood in terms of a more deadly new variant B1.1.7, while a decline in January correlates with vaccine roll-out, suggesting that vaccine reduce the severity of infection, as well as the risk.


Author(s):  
Marine Erasmus ◽  
Helen Kean

Background: This study contributes to the detailed understanding of the drivers of medical scheme expenditure on private hospitals in South Africa over 2006–2014. This is important in the context of various regulatory reforms that are being considered at present. Aim: The aim is to provide an updated analysis and description of the drivers of medical scheme expenditure on private hospitals in South Africa. Setting: Private hospital market, South Africa. Methods: Data from the three largest private hospital groups – which account for approximately 70% of the South African private hospital market share – are collected, aggregated and analysed. This study uses targeted descriptive and exploratory analyses, relying on a residual approach to hospital expenditure. Results: It is found that over time medical scheme beneficiaries, on average, are being admitted to private hospitals more frequently, as well as staying in hospital for longer during each admission. The data also indicate that over time older people are being admitted to hospital more often. Conclusion: This study’s findings contradict previous assertions that it is only prices driving increased medical scheme expenditure on private hospitals.


Koedoe ◽  
1990 ◽  
Vol 33 (2) ◽  
Author(s):  
W.S.W. Trollope

Veld management refers to the management of natural vegetation for specific objectives related to different forms of land use. In the wildlife context a wide spectrum of different forms of land use are practised ranging from pure nature conservation in large national parks through to smaller areas used for game farming. Consequently the products useable to society emanating from these areas vary greatly, and therefore the management of veld stocked with wildlife is extremely complex and must be adapted to the particular form of land use that is being practised. A generally accepted principle is that the smaller the area being used for wildlife the more intensively it must be managed, particularly game ranches. A prerequisite for the development of an effective veld management program is a comprehensive assessment of the condition of the veld upon which realistic veld management practices can be formulated. These practices will include stocking the veld with the appropriate species and numbers of animals, grazing and browsing management, veld burning and the provision of watering points. Finally a programme for monitoring veld condition over time is a prerequisite for sound veld management.


Land ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 227
Author(s):  
Menelisi Falayi ◽  
James Gambiza ◽  
Michael Schoon

The loss of ecosystem services through land degradation continues to be a significant concern for policymakers and land users around the world. Facilitating collective action among various actors is regarded as imperative in halting land degradation. Despite extensive research on collective action, there have been few studies that continuously map social ties and detect network evolution as a way of enabling longitudinal analysis of transformative spaces. This paper seeks to examine the changing dynamics of multi-actor and multi-level actor ties over a period of two years in Machubeni, South Africa. To do this, we used social network analysis to detect continuities and/or discontinuities of multi-actor and multi-level actor ties over time. Overall, edge density, clustering coefficient, and reciprocity scores steadily increased over the two years despite a decline in the number of active organisations within the network. Our results demonstrate that the proportion of strong ties gradually increased over time across three governance networks. However, multi-level linkages between the local municipality and the local organisations remained weak due to a lack of trust and collaborative fatigue. While the transformative space has succeeded in enhancing collaboration and knowledge sharing between local organisations and researchers, further long-term engagement with government agencies might be necessary for promoting institutional transformations and policy outcomes, and building network resilience in complex polycentric governance systems.


2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Erich Ritter ◽  
Raid Amin ◽  
Kevin Cahn ◽  
Jonathan Lee

The trends of the world’s top ten countries relating to shark bite rates, defined as the ratio of the annual number of shark bites of a country and its resident human population, were analyzed for the period 2000-2016. A nonparametric permutation-based methodology was used to determine whether the slope of the regression line of a country remained constant over time or whether so-called joinpoints, a core feature of the statistical software Joinpoint, occurred, at which the slope changes and a better fit could be obtained by applying a straight-line model. More than 90% of all shark bite incidents occurred along the US, Australia, South Africa, and New Zealand coasts. Since three of these coasts showed a negative trend when transformed into bite rates, the overall global trend is decreasing. Potential reasons for this decrease in shark bite rates—besides an increase in the world’s human population, resulting in more beach going people, and a decrease of sharks due to overfishing—are discussed.


2020 ◽  
Vol 10 (22) ◽  
pp. 7995
Author(s):  
Erik Möllerström ◽  
Daniel Lindholm

Based on data from 1162 wind turbines, with a rated power of at least 1.8 MW, installed in Sweden after 2005, the accuracy of the annual energy production (AEP) predictions from the project planning phases has been compared to the wind-index-corrected production. Both the production and the predicted AEP data come from the database Vindstat, which collects information directly from wind turbine owners. The mean error was 7.1%, which means that, overall, the predicted AEP has been overestimated. The overestimation was higher for wind turbines situated in open terrain than in forest areas and was higher overall than that previously established for the British Isles and South Africa. Dividing the result over the installation year, the improvement which had been expected due to the continuous refinement of the methods and better data availability, was not observed over time. The major uncertainty comes from the predicted AEP as reported by wind turbine owners to the Vindstat database, which, for some cases, might not come from the wind energy calculation from the planning phase (i.e., the P50-value).


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