146-453: The Alpha variant (B.1.1.7) was a SARS-CoV-2 variant of concern . It was estimated to be 40–80% more transmissible than the wild-type SARS-CoV-2 (with most estimates occupying the middle to higher end of this range). Scientists more widely took note of this variant in early December 2020, when a phylogenetic tree showing viral sequences from Kent , United Kingdom looked unusual. The variant began to spread quickly by mid-December, around
292-764: A variant of interest ( VOI ), or in some countries a variant under investigation ( VUI ). During or after fuller assessment as a variant of concern the variant is typically assigned to a lineage in the Pango nomenclature system and to clades in the Nextstrain and GISAID systems. Historically, the WHO regularly listed updates on variants of concern (VOC), which are variants with an increased rate of transmission, virulence, or resistance against mitigations, like vaccines. The variant submissions from member states are then submitted to GISAID , followed by field investigations of
438-481: A 95% confidence or credibility level, unless otherwise stated. Currently, all estimates are approximations due to the limited availability of data for studies. For Alpha, Beta, Gamma and Delta, there is no change in test accuracy , and neutralising antibody activity is retained by some monoclonal antibodies. PCR tests continue to detect the Omicron variant. The WHO defines a previously circulating variant as
584-509: A COVID‑19 vaccine candidate to boost its immunogenicity and efficacy to reduce or prevent COVID‑19 infection in vaccinated individuals. Adjuvants used in COVID‑;19 vaccine formulation may be particularly effective for technologies using the inactivated COVID‑19 virus and recombinant protein-based or vector-based vaccines. Aluminum salts, known as " alum ", were the first adjuvant used for licensed vaccines and are
730-481: A RT-PCR screening test and subsequently confirmed by genome sequencing, revealed that the variant grew from a share of 3.3% (388/11916) on 7–8 January (week 1) to 13.3% (475/3561) on 27 January (week 4), followed by 44.3% (273/615) on 16 February (week 7). In week 8, the variant was found to have a dominant share of 56.4% (758/1345) according to the interpretable results of a weekly genome sequencing survey comprising 0.9% of all COVID-19 positive tests, or 59.5% according to
876-545: A change from asparagine (N) to tyrosine (Y) in amino-acid position 501. This is because of its position inside the spike protein's receptor-binding domain (RBD)—more specifically inside the receptor-binding motif (RBM), a part of the RBD—which binds human ACE2 . Mutations in the RBD can change antibody recognition and ACE2 binding specificity and lead to the virus becoming more infectious ;. Chand et al. concluded that "[i]t
1022-492: A conclusion regarding disease severity. At prime minister Boris Johnson's briefing the following day, officials said that there was "no evidence" as of that date that the variant caused higher mortality or was affected differently by vaccines and treatments; Vivek Murthy agreed with this. Susan Hopkins , the joint medical adviser for the NHS Test and Trace and Public Health England (PHE), declared in mid-December 2020: "There
1168-464: A decade to develop. In contrast, mRNA is a molecule that can be made quickly, and research on mRNA to fight diseases was begun decades before the COVID‑19 pandemic by scientists such as Drew Weissman and Katalin Karikó , who tested on mice. Moderna began human testing of an mRNA vaccine in 2015. Viral vector vaccines were also developed for the COVID‑19 pandemic after the technology
1314-538: A factor of 1.74 14 / 6.5 = 3.3 {\displaystyle 1.74^{14/6.5}=3.3} every two weeks. Another group came to similar conclusions, generating a replicative advantage, independent of "protective measures", of 2.24 per generation of 6.73 days, out-competing the ancestral variant by 2.24 14 / 6.73 = 5.4 {\displaystyle 2.24^{14/6.73}=5.4} every two weeks. Similarly, in Ireland,
1460-552: A few nucleotides. Some of the potential consequences of emerging variants are the following: Variants that appear to meet one or more of these criteria may be labelled "variants under investigation" or "variants of interest" pending verification and validation of these properties. The primary characteristic of a variant of interest is that it shows evidence that demonstrates it is the cause of an increased proportion of cases or unique outbreak clusters; however, it must also have limited prevalence or expansion at national levels, or
1606-658: A mutation which may reduce vaccine effectiveness. On 9 February 2021, it became known that some 76 cases with the E484K mutation had been detected, principally in Bristol, but with a genomically distinct group in Liverpool also carrying the mutation. A week later a Research and analysis report from PHE gave a total of 77 confirmed and probable cases involving the E484K mutation across the UK, in two variants, VUI-202102/01 and VOC-202102/02,
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#17327985904841752-601: A nationwide weekly genome sequencing survey found that the Alpha variant grew from 0.05% (week 51) to a dominant 58.2% of cases in week 8, followed by 71.1% in week 9. This was in full accordance with a model from 9 February that had forecast dominance around mid-February. In comparison, the competing Beta variant was only found nationwide in 1.0% of the positive cases in week 9. In Belgium, genome sequencing of samples selected randomly after excluding all samples from active targeted testing related to local outbreaks or travels (creating
1898-673: A report published by PHE on 21 December 2020. In a report written on behalf of COVID-19 Genomics UK (COG-UK) Consortium , Andrew Rambaut and his co-authors, using the Phylogenetic Assignment of Named Global Outbreak Lineages (pangolin) tool, dubbed it lineage B.1.1.7 , while Nextstrain dubbed the variant 20I/501Y.V1 . The name VOC-202102/02 refers to the variant with the E484K mutation (see below ). Mutations in SARS-CoV-2 are common: over 4,000 mutations have been detected in its spike protein alone, according to
2044-573: A result of competition from even more infectious variants. In March 2022, the World Health Organization changed its designation to "previously circulating variant of concern". The variant is known by several names. Outside the UK it is sometimes referred to as the UK variant or British variant or English variant , despite the existence of other, less common, variants first identified in UK, such as Eta variant (lineage B.1.525). Within
2190-850: A robust T-cell response and their genes are more conserved and recombine less frequently (compared to Spike). Future generations of COVID‑19 vaccines that may target more conserved genomic regions will also act as insurance against the manifestation of catastrophic scenarios concerning the future evolutionary path of SARS-CoV-2, or any similar coronavirus epidemic/pandemic. Platforms developed in 2020 involved nucleic acid technologies ( nucleoside-modified messenger RNA and DNA ), non-replicating viral vectors , peptides , recombinant proteins , live attenuated viruses , and inactivated viruses . Many vaccine technologies being developed for COVID‑19 are not like influenza vaccines but rather use "next-generation" strategies for precise targeting of COVID‑19 infection mechanisms. Several of
2336-474: A second intranasal vaccine as a booster, trade name Pneucolin . Aivita Biomedical is developing an experimental autologous dendritic cell COVID‑19 vaccine kit where the vaccine is prepared and incubated at the point-of-care using cells from the intended recipient. The vaccine is undergoing small phase I and phase II clinical studies. A universal coronavirus vaccine would be effective against all coronaviruses and possibly other viruses. The concept
2482-410: A significant level, not having had a significant impact on the situation, or scientific evidence of the variant not having concerning properties. COVID-19 vaccine A COVID‑19 vaccine is a vaccine intended to provide acquired immunity against severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ), the virus that causes coronavirus disease 2019 ( COVID‑19 ). Before
2628-473: A single round of infection compared to [ wild-type SARS-CoV-2]" in lentiviral SARS-CoV-2 pseudoviruses . Using In Silico approach, Shahhosseini et al. demonstrated that the Y501 mutation in lineage B.1.1.7 forms a shorter H-bond (length of 2.94 Å) than its counterpart in the wild type (WT) variant residue N501, indicating that in lineage B.1.1.7 the RBD and hACE2 have a stable interaction. Furthermore,
2774-512: A spike ferritin-based nanoparticle (SpFN). This vaccine began a Phase I clinical trial in April 2022. Results of this trial were published in May 2024. Other universal vaccines that have entered clinical trial include OVX033 (France), PanCov (France), pEVAC-PS (UK), and VBI-2902 (Canada). Another strategy is to attach vaccine fragments from multiple strains to a nanoparticle scaffold. One theory
2920-478: A statistical representative national sample with a seize equal to 4.4% of all COVID-19 positive tests), found that the Alpha variant share grew from 7.1% in week 1 to a dominant 51.5% in week 7, followed by 79.3% in week 10. The variant was first time detected by targeted genome sequencing in week 49, but due to a small sample seize (not being random, and less than 100 tests per week) then no reliable variant share data could be determined before week 1. The proxy test for
3066-851: A supplementing first-screening test before conducting the whole-genome sequencing . As of 23 March, the Alpha variant had been detected in 125 out of 241 sovereign states and dependencies (or 104 out of 194 WHO member countries ), of which some had reported existence of community transmission while others so far only found travel related cases. As of 16 March, it had become the dominant COVID-19 variant for 21 countries: United Kingdom (week 52), Ireland (week 2), Bulgaria (week 4), Slovakia (week 5), Israel (week 5), Luxembourg (week 5), Portugal (week 6), Denmark (week 7), Netherlands (week 7), Norway (week 7), Italy (week 7), Belgium (week 7), France (week 8), Austria (week 8), Switzerland (week 8), Liechtenstein (week 9), Germany (week 9), Sweden (week 9), Spain (week 9), Malta (week 10) and Poland (week 11). The emergence and
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#17327985904843212-458: A variant that "has demonstrated to no longer pose a major added risk to global public health compared to other circulating SARS-CoV-2 variants", but should still be monitored. On 15 March 2023, the WHO released an update on the tracking system of VOCs, announcing that only VOCs will be assigned Greek letters. The variants listed below had previously been designated as variants of concern, but were displaced by other variants. As of May 2022 ,
3358-548: A variant-specific RT-PCR survey testing 54% of all the COVID-19 positive tests. In week 10, the variant was found to have a share of 71.9% according to a variant-specific RT-PCR survey testing 56.9% of all the COVID-19 positive tests. The spread of the variant differed regionally for the 96 departments located in Metropolitan France for week 10, with 91 departments over 50% and 5 departments with 30%-50% (of which
3504-406: A weekly genome sequencing revealed that the variant grew from 0.3% (week 51) to be dominant with a share of 53.0% in week 5, although results might not be fully representative due to the fact that no correction occurred from potential targeting bias from contact tracing, airport travellers and local outbreaks. Genome sequencing of a population representative randomized test pool - with no target bias -
3650-523: Is "no evidence" to suggest that the new variant would be resistant to the Pfizer–BioNTech vaccine currently being used in the UK's vaccination programme , and that people should still be protected. On 2 February 2021, Public Health England reported that they had detected "[a] limited number of B.1.1.7 VOC-202012/01 genomes with E484K mutations", which is also present in the Beta and Gamma variants;
3796-515: Is a common last name . In the event that the WHO uses the entirety of the Greek alphabet, the agency considered naming future variants after constellations . While there are many thousands of variants of SARS-CoV-2, subtypes of the virus can be put into larger groupings such as lineages or clades . Three main, generally used nomenclatures have been proposed: Each national public health institute may also institute its own nomenclature system for
3942-559: Is a descendant of B.1.1.28, the name B.1.1.28.1 is not permitted and thus the resultant name is P.1), and has 17 unique amino acid changes, 10 of which in its spike protein, including the three concerning mutations: N501Y , E484K and K417T. The N501Y and E484K mutations favour the formation of a stable RBD-hACE2 complex, thus, enhancing the binding affinity of RBD to hACE2. However, the K417T mutation disfavours complex formation between RBD and hACE2, which has been demonstrated to reduce
4088-565: Is also known as 20I (V1), 20I/501Y.V1 (formerly 20B/501Y.V1), or 501Y.V1. From October to December 2020, its prevalence doubled every 6.5 days, the presumed generational interval. It is correlated with a significant increase in the rate of COVID-19 infection in United Kingdom , associated partly with the N501Y mutation. There was some evidence that this variant had 40–80% increased transmissibility (with most estimates lying around
4234-461: Is currently no evidence that this strain causes more severe illness, although it is being detected in a wide geography, especially where there are increased cases being detected." Around a month later, however—on 22 January 2021—Johnson said that "there is some evidence that the new variant [VOC-202012/01]... may be associated with a higher degree of mortality", though Sir Patrick Vallance , the government's Chief Scientific Advisor , stressed that there
4380-642: Is currently not known when the index case or "patient zero" occurred, the choice of reference sequence for a given study is relatively arbitrary, with different notable research studies' choices varying as follows: The variant first sampled and identified in Wuhan, China is considered by researchers to differ from the progenitor genome by three mutations. Subsequently, many distinct lineages of SARS-CoV-2 have evolved. The following table presents information and relative risk level for currently and formerly circulating variants of concern (VOC). The intervals assume
4526-463: Is highly likely that N501Y affects the receptor-binding affinity of the spike protein, and it is possible that this mutation alone or in combination with the deletion at 69/70 in the N-terminal domain (NTD) is enhancing the transmissibility of the virus". In early 2021 a peer-reviewed paper found that the mentioned HV 69–70 deletion in vitro "appeared to have two-fold higher infectivity over
SARS-CoV-2 Alpha variant - Misplaced Pages Continue
4672-549: Is likely that infection with VOC B.1.1.7 is associated with an increased risk of hospitalisation and death compared to infection with non-VOC viruses". Results of the death studies were associated with some high uncertainty and confidence intervals, because of a limited sample size related to the fact that UK only analysed the VOC status for 8% of all COVID-19 deaths. A UK case-control study for 54,906 participants, testing positive for SARS-CoV-2 between 1 October 2020 and 29 January 2021 in
4818-480: Is more frequently resulting in serious illness in those cases. The South African health department also indicated that the variant may be driving the second wave of the COVID-19 epidemic in the country due to the variant spreading at a more rapid pace than other earlier variants of the virus. Scientists noted that the variant contains several mutations that allow it to attach more easily to human cells because of
4964-405: Is not yet enough evidence to be fully certain of this. In a paper analysing twelve different studies on lineage B.1.1.7 death rate relative to other lineages, it was found to have a higher death rate (71% according to LSHTM, 70% according to University of Exeter, 65% according to Public Health England, and 36% according to Imperial College London), and NERVTAG concluded: "Based on these analyses, it
5110-580: Is of the same lineage in the Pango nomenclature system, but has an additional E484K mutation. As of 17 March 2021, there were 39 confirmed cases of VOC -21FEB-02 in the UK. On 4 March 2021, scientists reported B.1.1.7 with E484K mutations in the state of Oregon . In 13 test samples analysed, one had this combination, which appeared to have arisen spontaneously and locally, rather than being imported. Other names for this variant include B.1.1.7+E484K and B.1.1.7 Lineage with S:E484K. On 18 December 2020,
5256-498: Is that a broader range of strains can be vaccinated against by targeting the receptor-binding domain, rather than the whole spike protein . As of September 2020 , eleven of the vaccine candidates in clinical development use adjuvants to enhance immunogenicity. An immunological adjuvant is a substance formulated with a vaccine to elevate the immune response to an antigen , such as the COVID‑19 virus or influenza virus. Specifically, an adjuvant may be used in formulating
5402-653: Is the same as Convidecia's only dose. In August 2021, the developers of Sputnik V proposed, in view of the Delta case surge, that Pfizer test the Ad26 component (termed its 'Light' version) as a booster shot. Inactivated vaccines consist of virus particles that are grown in culture and then killed using a method such as heat or formaldehyde to lose disease-producing capacity while still stimulating an immune response. Inactivated virus vaccines authorized in China include
5548-400: Is the virus that causes coronavirus disease 2019 (COVID-19). Some have been stated, to be of particular importance due to their potential for increased transmissibility, increased virulence, or reduced effectiveness of vaccines against them. These variants contribute to the continuation of the COVID-19 pandemic . As of 24 September 2024 , the variants of interest as specified by
5694-538: The 501.V2 variant , also known as 501.V2, 20H (V2), 20H/501Y.V2 (formerly 20C/501Y.V2), 501Y.V2, VOC-20DEC-02 (formerly VOC -202012/02), or lineage B.1.351, was first detected in South Africa and reported by the country's health department . It has been labelled as Beta variant by WHO. Researchers and officials reported that the prevalence of the variant was higher among young people with no underlying health conditions, and by comparison with other variants it
5840-805: The COVID-19 Genomics UK (COG-UK) Consortium . VOC-202012/01 is defined by 23 mutations: 14 non-synonymous mutations, 3 deletions, and 6 synonymous mutations (i.e., there are 17 mutations that change proteins and six that do not). Imperial College London investigated over a million people in England while the Alpha variant was dominant and discovered a wide range of further symptoms linked to Covid. "Chills, loss of appetite, headache and muscle aches" were most common in infected people, as well as classic symptoms. Several rapid antigen tests for SARS-CoV-2 are in widespread use globally for COVID-19 diagnostics. They are believed to be useful in stopping
5986-474: The COVID‑19 pandemic , an established body of knowledge existed about the structure and function of coronaviruses causing diseases like severe acute respiratory syndrome ( SARS ) and Middle East respiratory syndrome ( MERS ). This knowledge accelerated the development of various vaccine platforms in early 2020. The initial focus of SARS-CoV-2 vaccines was on preventing symptomatic, often severe, illness. In 2020,
SARS-CoV-2 Alpha variant - Misplaced Pages Continue
6132-510: The Moselle department in particular was notable due to finding a high 38.3% rate of the competing Beta variant, that - despite having declined from a dominant 54.4% value in week 8 - still was significantly above the 5.0% national average for this specific variant). In Austria, Agentur für Gesundheit und Ernährungssicherheit (AGES) collected data from N501Y RT-PCR specific tests combined with subsequent genome sequencing analysis, and found that
6278-550: The North Jutland Region to 96.1% in the Central Denmark Region . The observed growth of the relative variant share, was in full accordance with the earlier modelled forecast, that had predicted dominance (over 50%) around mid-February and a prevalence of around 80% of the total circulating variants by early March. In comparison, the genome sequencing only found the competing Beta variant in 0.4% of
6424-592: The Oxford–AstraZeneca COVID‑19 vaccine , the Sputnik V COVID‑19 vaccine , Convidecia , and the Janssen COVID‑19 vaccine . Convidecia and Janssen are both one-shot vaccines that offer less complicated logistics and can be stored under ordinary refrigeration for several months. Sputnik V uses Ad26 for its first dose, which is the same as Janssen's only dose, and Ad5 for the second dose, which
6570-669: The Oxford–AstraZeneca vaccine is effective against the Gamma variant, although the exact level of efficacy has not yet been released. Preliminary data from a study conducted by Instituto Butantan suggest that CoronaVac is effective against the Gamma variant as well, and as of July 2021 has yet to be expanded to obtain definitive data. On 16 March 2022, the WHO has de-escalated the Gamma variant and its subvariants to "previously circulating variants of concern". The Delta variant, also known as B.1.617.2, G/452R.V3, 21A or 21A/S:478K,
6716-645: The Robert Koch Institute (entitled RKI-Testzahlerfassung ), determined the share of circulating COVID-19 variants for the latest week by analysing 53,272 COVID-19 positive samples either by genome sequencing or RT-PCR proxy tests, with data collected on a voluntary basis from 84 laboratories from the university / research / clinical / outpatient sector - spread evenly across the nation. The survey did not utilize data weights or data selection criteria to ensure existence of geographical representativity, but might still be regarded as somewhat representative for
6862-852: The University of Cambridge said in a BBC interview that lineage B.1.525 appeared to have "significant mutations" already seen in some of the other newer variants, which means their likely effect is to some extent more predictable. On 18 February 2021, the Department of Health of the Philippines confirmed the detection of two mutations of COVID-19 in Central Visayas after samples from patients were sent to undergo genome sequencing. The mutations were later named as E484K and N501Y, which were detected in 37 out of 50 samples, with both mutations co-occurrent in 29 out of these. On 13 March,
7008-723: The World Health Organization are BA.2.86 and JN.1, and the variants under monitoring are JN.1.7, KP.2, KP.3, KP.3.1.1, JN.1.18, LB.1, and XEC. The origin of SARS-CoV-2 has not been identified. However, the emergence of SARS-CoV-2 may have resulted from recombination events between a bat SARS-like coronavirus and a pangolin coronavirus through cross-species transmission. The earliest available SARS-CoV-2 viral genomes were collected from patients in December 2019, and Chinese researchers compared these early genomes with bat and pangolin coronavirus strains to estimate
7154-413: The nasal mucosa , which is a portal for viral entry into the body. These vaccines are designed to stimulate nasal immune factors , such as IgA . In addition to inhibiting the virus, nasal vaccines provide ease of administration because no needles (or needle phobia ) are involved. A variety of intranasal COVID‑19 vaccines are undergoing clinical trials. The first authorised intranasal vaccine
7300-403: The Alpha variant (lineage B.1.1.7) were estimated to be under-reported by most countries as the most commonly used tests do not distinguish between this variant and other SARS-CoV-2 variants, and as many SARS-CoV-2 infections are not detected at all. RNA sequencing is required for detection of this variant, although RT-PCR test for specific variants can be used as a proxy test for Alpha — or as
7446-640: The Alpha variant accounted for 17.8% of cases nationwide on 4–5 February (week 5), followed by 54.0% on 18 February (week 7). The regional prevalence for week 7 ranged from 0% in Aosta Valley (although only one sample was tested) to 93.3% in Molise . In week 7, the competing Gamma variant had a prevalence of 4.3% (ranging between 0%-36.2% regionally) and the South African variant a prevalence of 0.4% (ranging between 0%-2.9% regionally). In Switzerland,
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#17327985904847592-592: The Beta variant. The variant regionally had its highest share in the county of Oslo and Viken , growing from 18% to 90% of analysed samples in Oslo from 20 January to 23 February (although with the data-corrected estimate a bit lower at 50-70% on 23 February); while growing from 21% to 80% of analysed samples in Viken from 25 January to 23 February (although with the data-corrected estimate a bit lower at 50% on 23 February). For
7738-934: The Chinese CoronaVac and the Sinopharm BIBP and WIBP vaccines; there is also the Indian Covaxin , the Russian CoviVac , the Kazakh vaccine QazVac , and the Iranian COVIran Barekat . Vaccines in clinical trials include the Valneva COVID‑;19 vaccine . Subunit vaccines present one or more antigens without introducing whole pathogen particles. The antigens involved are often protein subunits , but they can be any molecule fragment of
7884-491: The Delta variant occurred among the fully vaccinated. In June 2021, reports began to appear of a variant of Delta with the K417N mutation. The mutation, also present in the Beta and Gamma variants, raised concerns about the possibility of reduced effectiveness of vaccines and antibody treatments and increased risk of reinfection. The variant, called "Delta with K417N" by Public Health England, includes two clades corresponding to
8030-712: The Department of Health confirmed the mutations constitutes a variant which was designated as lineage P.3. On the same day, it also confirmed the first COVID-19 case caused by the Gamma variant in the country. The Philippines had 98 cases of the Theta variant on 13 March. On 12 March it was announced that Theta had also been detected in Japan. On 17 March, the United Kingdom confirmed its first two cases, where PHE termed it VUI-21MAR-02. On 30 April 2021, Malaysia detected 8 cases of
8176-576: The Epsilon variant accounted for 36 per cent of samples collected at Cedars-Sinai Medical Center, and by January 2021, the Epsilon variant accounted for 50 per cent of samples. In a joint press release by University of California, San Francisco , California Department of Public Health , and Santa Clara County Public Health Department , the variant was also detected in multiple counties in Northern California. From November to December 2020,
8322-729: The European Union. Authorized vaccines of this type include the Pfizer–BioNTech and Moderna vaccines. The CVnCoV RNA vaccine from CureVac failed in clinical trials. Severe allergic reactions are rare. In December 2020, 1,893,360 first doses of Pfizer–BioNTech COVID‑19 vaccine administration resulted in 175 cases of severe allergic reactions, of which 21 were anaphylaxis . For 4,041,396 Moderna COVID‑19 vaccine dose administrations in December 2020 and January 2021, only ten cases of anaphylaxis were reported. Lipid nanoparticles (LNPs) were most likely responsible for
8468-670: The L452R (previously also detected in other unrelated lineages) was of particular concern. From 17 March to 29 June 2021, the CDC listed B.1.429 and the related B.1.427 as "variants of concern". As of July 2021, Epsilon is no longer considered a variant of interest by the WHO, as it was overtaken by Alpha. From September 2020 to January 2021, it was 19% to 24% more transmissible than earlier variants in California. Neutralisation against it by antibodies from natural infections and vaccinations
8614-495: The ORF8 gene noted that they "have been associated to milder symptoms and better disease outcome". The study also noted that "SARS-CoV-2 ORF8 is an immunoglobulin (Ig)–like protein that modulates pathogenesis ", that "SARS-CoV-2 ORF8 mediates major histocompatibility complex I (MHC-I) degradation", and that "SARS-CoV-2 ORF8 suppresses type I interferon (IFN)–mediated antiviral response". Referring to amino-acid position 501 inside
8760-463: The Pango lineages AY.1 and AY.2. It has been nicknamed "Delta plus" from "Delta plus K417N". The name of the mutation, K417N, refers to an exchange whereby lysine (K) is replaced by asparagine (N) at position 417. On 22 June, India's Ministry of Health and Family Welfare declared the "Delta plus" variant of COVID-19 a variant of concern, after 22 cases of the variant were reported in India. After
8906-502: The S2 domain of the spike protein). As of 5 March 2021, it had been detected in 23 countries. It has also been reported in Mayotte , the overseas department/region of France. The first cases were detected in December 2020 in the UK and Nigeria, and as of 15 February 2021, it had occurred in the highest frequency among samples in the latter country. As of 24 February 56 cases were found in
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#17327985904849052-720: The Spike RBD and ACE2, the N501Y mutation was found to significantly enhance the binding affinity between the RBD and ACE2 by approximately 10-fold, resulting from a 1.8-fold increase in the association rate constant (kon) and a 7-fold decrease in the dissociation rate constant (koff). Matched cohort studies of the Alpha variant (lineage B.1.1.7) found higher mortality rate than earlier circulating variants overall, but not in hospitalised patients. An ecological study found no difference in mortality overall. Initially, NERVTAG said on 18 December 2020 that there were insufficient data to reach
9198-559: The Theta variant in Sarawak. As of July 2021, Theta is no longer considered a variant of interest by the WHO. The proportion of USA cases represented by the Iota variant had declined sharply by the end of July 2021 as the Delta variant became dominant. The variants listed below were once listed under variants under monitoring, but were reclassified due to either no longer circulating at
9344-537: The UK in nearly 60 different local authorities. These cases were predominantly in the south east of England . The variant has also been identified in Wales and Scotland. By November, around a quarter of cases in the COVID-19 pandemic in London were being caused by the new variant, and by December, that was a third. In mid-December, it was estimated that almost 60 percent of cases in London involved Alpha. By 25 January 2021,
9490-463: The UK, it is commonly referred to as the Kent variant after Kent , where the variant was found. In scientific use, the variant had originally been named the first Variant Under Investigation in December 2020 (VUI – 202012/01) by Public Health England (PHE), but was reclassified to a Variant of Concern ( Variant of Concern 202012/01 , abbreviated VOC-202012/01 ) by Meera Chand and her colleagues in
9636-432: The UK. Denmark, which sequences all its COVID-19 cases, found 113 cases of this variant from 14 January to 21 February 2021, of which seven were directly related to foreign travel to Nigeria. As of July 2021, UK experts are studying it to ascertain how much of a risk it could be. It is currently regarded as a "variant under investigation", but pending further study, it may become a " variant of concern ". Ravi Gupta , from
9782-561: The United States beginning in fall 2024 should be monovalent JN.1 vaccines. Since January 2020, vaccine development has been expedited via unprecedented collaboration in the multinational pharmaceutical industry and between governments. Multiple steps along the entire development path are evaluated, including: There have been several unique challenges with COVID‑19 vaccine development. Public health programs have been described as "[a] race to vaccinate individuals" with
9928-416: The WHO as alpha , beta , gamma , delta and omicron variants. Early in the pandemic, the relatively low number of infections (compared with later stages of the pandemic) resulted in fewer opportunities for mutation of the viral genome and, therefore, fewer opportunities for the occurrence of differentiated variants. Since the occurrence of variants was rarer, the observation of S-protein mutations in
10074-441: The WHO did so on 7 June 2022. As of 15 March 2023 , The WHO defines a VOI as a variant "with genetic changes that are predicted or known to affect virus characteristics such as transmissibility, virulence, antibody evasion, susceptibility to therapeutics and detectability" and that is circulating more than other variants in over one WHO region to such an extent that a global public health risk can be suggested. Furthermore,
10220-514: The WHO lists the following under "previously circulating variants of concern": First detected in October 2020 during the COVID-19 pandemic in the United Kingdom from a sample taken the previous month in Kent, lineage B.1.1.7, labelled Alpha variant by the WHO, was previously known as the first Variant Under Investigation in December 2020 (VUI – 202012/01) and later notated as VOC-202012/01. It
10366-448: The Y501 mutation in lineage B.1.1.7 contributes more negatively to Binding Free Energy (BFE) (-7.18 kcal/mol) than its counterpart in the WT variant residue N501 (-2.92 kcal/mol). As a result of combining BFE and molecular interaction results, the N501Y mutation in RBD strengthens binding affinity of SARS-CoV-2 RBD to hACE2. In a detailed affinity and kinetic analysis of the interaction between
10512-560: The actual impact on the course of the disease is uncertain. A pre-print study by the Oswaldo Cruz Foundation published in early April found that the real-world performance of people with the initial dose of the Sinovac 's Coronavac Vaccine had approximately 50% efficacy rate. They expected the efficacy to be higher after the 2nd dose. As of July 2021, the study is ongoing. Preliminary data from two studies indicate that
10658-458: The adjuvant of choice in some 80% of adjuvanted vaccines. The alum adjuvant initiates diverse molecular and cellular mechanisms to enhance immunogenicity, including the release of proinflammatory cytokines. In June 2024, the US Food and Drug Administration (FDA) advised the manufacturers of the licensed and authorized COVID-19 vaccines that the COVID-19 vaccines (2024-2025 Formula) for use in
10804-408: The age distribution of cases, or disease severity. Data seen by NERVTAG indicated that the relative reproduction number ("multiplicative advantage") was determined to be 1.74—i.e., the variant is 74% more transmissible—assuming a 6.5-day generational interval. It was demonstrated that the variant grew fast exponentially with respect to the other variants. The variant out-competed the ancestral variant by
10950-430: The allergic reactions. These vaccines are examples of non-replicating viral vector vaccines using an adenovirus shell containing DNA that encodes a SARS‑CoV‑2 protein. The viral vector-based vaccines against COVID‑19 are non-replicating, meaning that they do not make new virus particles but rather produce only the antigen that elicits a systemic immune response. Authorized vaccines of this type include
11096-439: The ancestral human coronavirus type; the identified ancestral genome type was labeled "S", and its dominant derived type was labeled "L" to reflect the mutant amino acid changes. Independently, Western researchers carried out similar analyses but labeled the ancestral type "A" and the derived type "B". The B-type mutated into further types including B.1, which is the ancestor of the major global variants of concern, labeled in 2021 by
11242-474: The announcement, leading virologists said there was insufficient data to support labelling the variant as a distinct variant of concern, pointing to the small number of patients studied. In the UK in July 2021, AY.4.2 was identified. Alongside those previously mentioned it also gained the nickname 'Delta Plus', on the strength of its extra mutations, Y145H and A222V. These are not unique to it, but distinguish it from
11388-460: The availability of hospital services over time and space. A Danish study found people infected by lineage B.1.1.7 to be 64% (32%–104%) more likely to get admitted to hospitals compared with people infected by another lineage. Genetic sequencing of VOC-202012/01 has shown a Q27stop mutation which "truncates the ORF8 protein or renders it inactive". An earlier study of SARS-CoV-2 variants which deleted
11534-523: The average growth for all other variants by the end of this two week period. The variant became the dominant variant in London, East of England and the South East from low levels in one to two months. A surge of SARS-CoV-2 infections around the start of the new year is seen as being the result of the elevated transmissibility of the variant, while the other variants were in decline. One of the most important changes in lineage B.1.1.7 seems to be N501Y ,
11680-469: The binding affinity. The new variant was absent in samples collected from March to November 2020 in Manaus , Amazonas state, but it was detected for the same city in 42% of the samples from 15 to 23 December 2020, followed by 52.2% during 15–31 December and 85.4% during 1–9 January 2021. A study found that infections by Gamma can produce nearly ten times more viral load compared to persons infected by one of
11826-464: The body how to identify and destroy the corresponding pathogen. RNA vaccines often use nucleoside-modified messenger RNA . The delivery of mRNA is achieved by a coformulation of the molecule into lipid nanoparticles , which protect the RNA strands and help their absorption into the cells. RNA vaccines are the first COVID‑19 vaccines to be authorized in the United Kingdom, the United States, and
11972-653: The chain of transmission of the virus by providing the means to rapidly identify large numbers of cases as part of a mass-testing program. Following the emergence of VOC-202012/01, there was initially concern that rapid tests might not detect it, but Public Health England determined that rapid tests evaluated and used in the United Kingdom detected the variant. By late 2020, several COVID-19 vaccines were being deployed or under development. However, as further mutations occurred, concerns were raised as to whether vaccine development would need to be altered. SARS-CoV-2 does not mutate as quickly as, for example, influenza viruses , and
12118-459: The classification would be elevated to a " variant of concern ". If there is clear evidence that the effectiveness of prevention or intervention measures for a particular variant is substantially reduced, that variant is termed a "variant of high consequence". SARS-CoV-2 variants are grouped according to their lineage and component mutations. Many organisations, including governments and news outlets, referred colloquially to concerning variants by
12264-568: The community and in care and nursing homes, found a hazard ratio of 1.61 (95% confidence interval 1.42–1.82) for death within 28 days of testing among individuals infected with lineage B.1.1.7; no significant differences in the increased hazard of death associated with lineage B.1.1.7 were found among individuals differing in age, sex, ethnicity, deprivation level, or place of residence. Both studies adjusted for varying COVID-19 mortality by geographical region and over time, correcting for potential biases due to differences in testing rates or differences in
12410-517: The community setting (not including vulnerable persons from care centres and other public institutions), reported that patients infected with the Alpha variant (VOC 202012/1) had a hazard ratio for death within 28 days of testing of 1.64 (95% confidence interval 1.32-2.04), as compared with matched patients positive for other variants of SARS-CoV-2. Also in the UK, a survival analysis of 1,146,534 participants testing positive for SARS-CoV-2 between 1 November 2020 and 14 February 2021, including individuals in
12556-405: The country in which they were first identified. After months of discussions, the World Health Organization announced Greek-letter names for important strains on 31 May 2021, so they could be easily referred to in a simple, easy to say, and non-stigmatising fashion. This decision may have partially been taken because of criticism from governments on using country names to refer to variants of
12702-501: The doses purchased by high-income countries comprising 14% of the world's population. Despite the extremely rapid development of effective mRNA and viral vector vaccines , worldwide vaccine equity has not been achieved. The development and use of whole inactivated virus (WIV) and protein-based vaccines have also been recommended, especially for use in developing countries . The 2023 Nobel Prize in Physiology or Medicine
12848-735: The elderly, and those at high risk of exposure and transmission, such as healthcare workers. Common side effects of COVID‑19 vaccines include soreness, redness, rash, inflammation at the injection site, fatigue, headache, myalgia (muscle pain), and arthralgia (joint pain), which resolve without medical treatment within a few days. COVID‑19 vaccination is safe for people who are pregnant or are breastfeeding. As of 12 August 2024 , 13.72 billion doses of COVID‑19 vaccines have been administered worldwide, based on official reports from national public health agencies . By December 2020, more than 10 billion vaccine doses had been preordered by countries, with about half of
12994-470: The elderly, children, pregnant women , and people with weakened immune systems . Several COVID‑19 vaccines, such as the Pfizer–BioNTech and Moderna vaccines, use RNA to stimulate an immune response. When introduced into human tissue, the vaccine contains either self-replicating RNA or messenger RNA (mRNA), which both cause cells to express the SARS-CoV-2 spike protein . This teaches
13140-741: The face of rising population immunity, either by infection recovery or via vaccination. Some of the variants of concern show mutations in the RBD of the S-protein. The term variant of concern ( VOC ) for SARS-CoV-2 , which causes COVID-19 , is a category used for variants of the virus where mutations in their spike protein receptor binding domain (RBD) substantially increase binding affinity (e.g., N501Y) in RBD-hACE2 complex (genetic data), while also being linked to rapid spread in human populations (epidemiological data). Before being allocated to this category, an emerging variant may have been labeled
13286-429: The family Coronaviridae that affect humans have been aimed at severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Vaccines against SARS and MERS have been tested in non-human animals . According to studies published in 2005 and 2006, the identification and development of novel vaccines and medicines to treat SARS was a priority for governments and public health agencies around
13432-586: The fast spreading of the new variant has been detected in Lebanon and a relationship noted between SARS-CoV-2 transmission intensity and the frequency of the new variant during the first twelve days of January. By February, Alpha became the dominant variant in Lebanon. The first case was likely in mid-September 2020 in London or Kent , United Kingdom. The variant was sequenced in September. As of 13 December 2020, 1,108 cases with this variant had been identified in
13578-488: The first COVID‑19 vaccines were developed and made available to the public through emergency authorizations and conditional approvals. Initially, most COVID‑19 vaccines were two-dose vaccines, with the exception single-dose vaccines Convidecia and the Janssen COVID‑19 vaccine , and vaccines with three-dose schedules, Razi Cov Pars and Soberana . However, immunity from the vaccines has been found to wane over time, requiring people to get booster doses of
13724-527: The following three mutations in the receptor-binding domain (RBD) in the spike glycoprotein of the virus: N501Y , K417N, and E484K . The N501Y mutation has also been detected in the United Kingdom. On 16 March 2022, the WHO has de-escalated the Beta variant and its subvariants to "previously circulating variants of concern". The Gamma variant or lineage P.1, termed Variant of Concern 21JAN-02 (formerly VOC-202101/02) by Public Health England, 20J (V3) or 20J/501Y.V3 by Nextstrain , or just 501Y.V3,
13870-482: The frequency of the variant in sequenced cases from Northern California rose from 3% to 25%. In a preprint, CAL.20C is described as belonging to clade 20C and contributing approximately 36% of samples, while an emerging variant from the 20G clade accounts for some 24% of the samples in a study focused on Southern California. Note, however, that in the US as a whole, the 20G clade predominates, as of January 2021. Following
14016-516: The immune system and lessen the severity of COVID‑19 infections. There is experimental evidence that the BCG vaccine for tuberculosis has non-specific effects on the immune system, but there is no evidence that this vaccine is effective against COVID‑19. Most coronavirus vaccines are administered by injection, with further vaccine delivery methods being studied for future coronavirus vaccines. Intranasal vaccines target mucosal immunity in
14162-600: The increasing numbers of Epsilon in California, the variant has been detected at varying frequencies in most US states. Small numbers have been detected in other countries in North America, and in Europe, Asia and Australia. After an initial increase, its frequency rapidly dropped from February 2021 as it was being outcompeted by the more transmissible Alpha . In April, Epsilon remained relatively frequent in parts of northern California, but it had virtually disappeared from
14308-510: The latter described as 'B.1.1.7 with E484K'. On 5 March 2021, it was reported that a B.1.1.7 lineage with the E484K mutation has been detected in two US patients (in Oregon and New York states). Researchers thought that the E484K mutation in the Oregon variant arose independently. The transmissibility of the Alpha variant (lineage B.1.1.7) had generally been found to be substantially higher than that of pre-existing SARS-CoV-2 variants. The variant
14454-523: The method used to assess increases in transmissibility. Similar increases in the transmissibility of lineage B.1.1.7 were measured in Denmark , Switzerland , and the United States . Furthermore, a simple model to account for the rapid rise of lineage B.1.1.7 in several countries and the world found that the variant is 50% more transmissible than the local wild type in these three countries and across
14600-510: The middle to higher end of this range), and early analyses suggested an increase in lethality, though later work found no evidence of increased virulence. As of May 2021, the Alpha variant had been detected in some 120 countries. On 16 March 2022, the WHO has de-escalated the Alpha variant and its subvariants to "previously circulating variants of concern". Variant of Concern 21FEB-02 (previously written as VOC -202102/02), described by Public Health England (PHE) as "B.1.1.7 with E484K"
14746-508: The national average due to its big sample seize. According to the RKI-Testzahlerfassung survey, the variant grew from a share of 2.0% (week 2) to a dominant share of 54.5% (week 9), followed by 63.5% in week 10. In comparison, the competing Beta variant was only found nationwide in 0.9% of the positive cases in week 10. In Malta, the variant was first time detected by genome sequencing on 30 December 2020, and represented 8% of
14892-501: The new vaccines that had proved effective by the end of 2020 are types that can be adjusted if necessary. As of the end of 2020, German, British, and American health authorities and experts believe that existing vaccines will be as effective against VOC-202012/01 as against previous variants. On 18 December, NERVTAG determined "that there are currently insufficient data to draw any conclusion on... [a]ntigenic escape ". As of 20 December 2020, Public Health England confirmed there
15038-644: The number of confirmed and probable UK cases had grown to 28,122. The variant became dominant for: In Bulgaria, genome sequencing found the variant to be dominant with 52.1% in week 4, followed by 73.4% in week 9. Also in Slovakia, a RT-PCR Multiplex DX test capable of detecting the 2 deletions specific for lineage B.1.1.7 (ΔH69/ΔV70 and ΔY144), first found the variant nationwide in 74% of cases on 3 February (week 5), followed by 72% of cases on 15 February (week 7), and it then grew to 90% of cases on 3 March (week 9). The same test found earlier on 8 January prevalence of
15184-461: The original Delta variant. On 7 June 2022, the WHO has de-escalated the Delta variant and its subvariants to "previously circulating variants of concern". The Epsilon variant or lineage B.1.429, also known as CAL.20C or CA VUI1, 21C or 20C/S:452R, is defined by five distinct mutations (I4205V and D1183Y in the ORF1ab gene, and S13I, W152C, L452R in the spike protein's S-gene), of which
15330-602: The original version of the virus and could spread quicker or as quickly as Alpha. It carries L452R and P681R mutations in Spike; unlike Kappa it carries T478K but not E484Q. On 3 June 2021, Public Health England reported that twelve of the 42 deaths from the Delta variant in England were among the fully vaccinated, and that it was spreading almost twice as fast as the Alpha variant. Also on 11 June, Foothills Medical Centre in Calgary, Canada reported that half of their 22 cases of
15476-544: The other lineages identified in Brazil (B.1.1.28 or B.1.195). Gamma also showed 2.2 times higher transmissibility with the same ability to infect both adults and older persons, suggesting P.1 and P.1-like lineages are more successful at infecting younger humans irrespective of sex. A study of samples collected in Manaus between November 2020 and January 2021, indicated that the Gamma variant is 1.4–2.2 times more transmissible and
15622-516: The pathogen. The authorized vaccines of this type include the peptide vaccine EpiVacCorona , ZF2001 , MVC-COV1901 , Corbevax , the Sanofi–GSK vaccine , and Soberana 02 (a conjugate vaccine ). Bimervax (selvacovatein) was approved for use as a booster vaccine in the European Union in March 2023. The V451 vaccine was in clinical trials that were terminated after it was found that
15768-408: The period 15 February to 14 March, the combined survey of genome sequencing and PCR proxy tests, also found the Alpha variant was at a dominant rate over 50% for 8 out of 11 regions, with its highest rate (82%) found for Oslo; while the region Nordland was different from all other regions by having only 6% cases of Alpha along with a dominant 88% of cases represented by the Beta variant. In Portugal,
15914-399: The platforms of vaccine candidates in clinical trials are focused on the coronavirus spike protein (S protein) and its variants as the primary antigen of COVID‑19 infection, since the S protein triggers strong B-cell and T-cell immune responses. However, other coronavirus proteins are also being investigated for vaccine development, like the nucleocapsid , because they also induce
16060-495: The positive cases (9 times out of 2315 tests) in week 10. In the Netherlands, a randomly conducted genome sequencing found that the variant grew from 1.3% of cases in week 49 to a dominant share of 61.3% in week 7, followed by 82.0% in week 9; while the competing Beta variant in comparison was found to be at 3.0% in week 9. In Amsterdam, the Alpha variant (lineage B.1.1.7) grew from 5.2% (week 52) to 54.5% (week 6). In Norway,
16206-479: The positive cases in week 7. A new RT-PCR variant specific test was introduced for the surveillance, where the first results reported on 10 March revealed the variant now represented 61% of cases nationwide. Variants of SARS-CoV-2 Variants of severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ) are viruses that, while similar to the original, have genetic changes that are of enough significance to lead virologists to label them separately. SARS-CoV-2
16352-412: The purposes of tracking specific variants. For example, Public Health England designated each tracked variant by year, month and number in the format [YYYY] [MM]/[NN], prefixing 'VUI' or 'VOC' for a variant under investigation or a variant of concern respectively. This system has now been modified and now uses the format [YY] [MMM]-[NN], where the month is written out using a three-letter code. As it
16498-550: The receptor-binding domain (RBD) region interacting with ACE2 was also not frequent. As time went on, the evolution of SARS-CoV-2's genome (by means of random mutations) led to mutant specimens of the virus (i.e., genetic variants), observed to be more transmissible, to be naturally selected. Notably, both the Alpha and the Delta variants were observed to be more transmissible than previously identified viral strains. Some SARS-CoV-2 variants are considered to be of concern as they maintain (or even increase) their replication fitness in
16644-505: The same E484K-mutation as found in the Gamma, Zeta, and Beta variants, and also carries the same ΔH69/ΔV70 deletion (a deletion of the amino acids histidine and valine in positions 69 and 70) as found in Alpha, N439K variant (B.1.141 and B.1.258) and Y453F variant ( Cluster 5 ). Eta differs from all other variants by having both the E484K-mutation and a new F888L mutation (a substitution of phenylalanine (F) with leucine (L) in
16790-412: The same time as infections surged. This increase is thought to be at least partly because of one or more mutations in the virus' spike protein . The variant was also notable for having more mutations than normally seen. By January 2021, more than half of all genomic sequencing of SARS-CoV-2 was carried out in the UK. This gave rise to questions as to how many other important variants were circulating around
16936-499: The south of the state and had never been able to establish a foothold elsewhere; only 3.2% of all cases in the United States were Epsilon, whereas more than two-thirds were Alpha. The Eta variant or lineage B.1.525, also called VUI -21FEB-03 (previously VUI-202102/03) by Public Health England (PHE) and formerly known as UK1188, 21D or 20A/S:484K, does not carry the same N501Y mutation found in Alpha , Beta and Gamma , but carries
17082-488: The spike protein, Chand et al. concluded that "it is possible that variants at this position affect the efficacy of neutralisation of virus", but noted that "[t]here is currently no neutralisation data on N501Y available from polyclonal sera from natural infection". The HV 69–70 deletion has, however, been discovered "in viruses that eluded the immune response in some immunocompromised patients", and has also been found "in association with other RBD changes". Cases of
17228-413: The synthetic vaccines use a 2P mutation to lock the spike protein into its prefusion configuration, stimulating an adaptive immune response to the virus before it attaches to a human cell. Vaccine platforms in development may improve flexibility for antigen manipulation and effectiveness for targeting mechanisms of COVID‑19 infection in susceptible population subgroups, such as healthcare workers,
17374-485: The transmissibility of lineage B.1.1.7 based on the weekly development of its observed fraction of all Covid-19 positives during the entire pandemic, and found for 95% confidence intervals under the assumption of a wildtype reproduction number Rw≈1 and an exponentially generation time of 5.2 days, that transmissibility was: 52% (45%–60%) higher when compared to the wildtype in Denmark and 51% (42%-60%) higher when compared to
17520-466: The transmissibility rate of the variant compared to the local wildtype, and found it to fluctuate between 28%-47% higher during the first six weeks of 2021. The Danish Statens Serum Institut in comparison calculated it to be 55% (48%–62%) more transmissible in Denmark based upon the observed development of its relative frequency from 4 January to 12 February 2021. The Institute of Social and Preventive Medicine (ISPM) under University of Bern , calculated
17666-403: The update stated that "VOIs will be referred to using established scientific nomenclature systems such as those used by Nextstrain and Pango". Viruses generally acquire mutations over time, giving rise to new variants. When a new variant appears to be growing in a population, it can be labelled as an "emerging variant". In the case of SARS-CoV-2, new lineages often differ from one another by just
17812-615: The vaccine may potentially cause incorrect results for subsequent HIV testing. The authorized vaccines of this type include the Novavax COVID‑19 vaccine . Additional types of vaccines that are in clinical trials include multiple DNA plasmid vaccines , at least two lentivirus vector vaccines, a conjugate vaccine , and a vesicular stomatitis virus displaying the SARS‑CoV‑2 spike protein. Scientists investigated whether existing vaccines for unrelated conditions could prime
17958-535: The vaccine to maintain protection against COVID‑19. The COVID‑19 vaccines are widely credited for their role in reducing the spread of COVID‑19 and reducing the severity and death caused by COVID‑19. According to a June 2022 study, COVID‑19 vaccines prevented an additional 14.4 to 19.8 million deaths in 185 countries and territories from 8 December 2020 to 8 December 2021. Many countries implemented phased distribution plans that prioritized those at highest risk of complications, such as
18104-518: The variant (RT-PCR SGTF) was also conducted for a sample seize equal to 25.8% of all COVID-19 positive tests, and found a dominant 54.8% SGTF rate for week 10. In comparison, the competing Beta variant was found to be at 3.6% and the Gamma variant had a prevalence of 1.8% in week 10. In France, scientists accurately forecast the Alpha variant (VOC-202012/01) would likely become dominant nationwide around week 8–11 of 2021. A nationwide survey of randomly selected positive COVID-19 samples first analysed by
18250-613: The variant at a rate of 36% in the Michalovce District and 29% in Nitra . In Israel, the variant was first time detected by genome sequencing 23 December 2020. Leumit Health Care Services however analysed with the proxy test RT-PCR (SGTF) and found the variant at a rate of 3‑4% on 15 December. The national Ministry of Health estimated based on genome sequencing, that the prevalence of the variant became dominant (70%) on 6 February followed by 90% on 16 February. In Luxembourg,
18396-443: The variant grew from 7.2% (week 1) to a dominant 61.3% (week 8), followed by 61.2% in week 9 and 48.3% in week 10. If all N501Y positive tests had been analysed further by genome sequencing, then these listed shares could have been even higher, for example they could have been as mcuh as: 2.4% higher for week 1, 23.0% higher for week 7, 4.0% higher for week 8, 6.8% higher for week 9 and 25.4% higher for week 10. The competing Beta variant
18542-612: The variant represented according to a national genome sequencing survey: 16.0% of the Covid-19 infections during 10–19 January (week 2), followed by a dominant 58.2% in week 6. A national RT-PCR proxy test based on SGTF and SGTL observations, found the variant at a rate of 33.5% in week 4, but observed afterwards a decelerating pace for the weekly rise of the variant share (reason unknown), and according to this study it only became dominant by 50.5% (91.8% of 55.0% SGTFL) in week 8, followed by 64.3% (91.8% of 70% SGTFL) in week 10. In Italy,
18688-478: The variant was found by genome sequencing to grow from 5.7% (week 1) into dominance by a 58.4% (week 7), followed by 65.0% (week 8). Another large survey comprising results of both genome sequencing and PCR proxy tests, with a sample seize of more than 1000 tests per week (since week 4), at the same time found that the variant grew from 2.0% (week 48) into dominance by 60.0% (week 7), followed by 72.7% in week 10 - while only 2.2% of cases in comparison were found to be of
18834-465: The variant. Updated definitions, published on the 4 October 2023, add variants of interest (VOI) and variants under monitoring (VUM) to the World Health Organization's working definitions for SARS-CoV-2 variants. Other organisations such as the CDC in the United States typically define their variants of concern slightly differently; for example, the CDC de-escalated the Delta variant on 14 April 2022, while
18980-647: The variant—as indicated by the missing S gene detection ( S-gene target failure [SGTF]), which historically was rare—went from 16.3% to 46.3% of cases in two weeks. This demonstrates, based on the statistics of 116 positive samples, that the variant had a relative higher growth by a factor of 46.3 % ⋅ ( 100 % − 16.3 % ) / ( ( 100 % − 46.3 % ) ⋅ 16.3 % ) = 4.4 {\displaystyle 46.3\%\cdot (100\%-16.3\%)/((100\%-46.3\%)\cdot 16.3\%)=4.4} , when compared to
19126-486: The virus; the WHO mentioned the potential for mentioning country names to cause stigma. After using all the letters from Alpha to Mu (see below), in November 2021 the WHO skipped the next two letters of the Greek alphabet, Nu and Xi, and used Omicron, prompting speculation that Xi was skipped to avoid offending Chinese leader Xi Jinping . The WHO gave as the explanation that Nu is too easily confounded with "new" and Xi
19272-589: The wildtype in Switzerland. On 18 December 2020—early on in the risk assessment of the variant—the UK scientific advisory body New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG) concluded that they had moderate confidence that VOC-202012/01 was substantially more transmissible than other variants, but that there were insufficient data to reach any conclusion on underlying mechanism of increased transmissibility (e.g. increased viral load, tissue distribution of virus replication, serial interval etc.),
19418-435: The world as whole. Another study concluded that it was 75% (70%–80%) more transmissible in the UK between October and November 2020. A later study suggested that these earlier estimates overestimated the transmissibility of the variant and that the transmissibility increase was on the lower ends of these ranges. The Dutch Ministry of Health, Welfare and Sport calculated, based on genome sequencing of positive cases, each week
19564-720: The world at that time. There is no cure or protective vaccine proven to be safe and effective against SARS in humans. There is also no proven vaccine against MERS. When MERS became prevalent, it was believed that existing SARS research might provide a useful template for developing vaccines and therapeutics against a MERS-CoV infection. As of March 2020, there was one (DNA-based) MERS vaccine that completed Phase I clinical trials in humans, and three others in progress, all being viral-vectored vaccines: two adenoviral-vectored (ChAdOx1-MERS, BVRS-GamVac) and one MVA -vectored (MVA-MERS-S). Vaccines that use an inactive or weakened virus that has been grown in eggs typically take more than
19710-577: The world undetected. On 2 February 2021, Public Health England reported that they had detected "[a] limited number of B.1.1.7 VOC-202012/01 genomes with E484K mutations", which they dubbed Variant of Concern 202102/02 (VOC-202102/02). One of the mutations ( N501Y ) was also present in Beta variant and Gamma variant . On 31 May 2021, the World Health Organization announced that the Variant of Concern would be labelled "Alpha" for use in public communications. The Alpha variant disappeared in late 2021 as
19856-505: Was Razi Cov Pars in Iran at the end of October 2021. The first viral component of Sputnik V vaccine was authorised in Russia as Sputnik Nasal in April 2022. In September 2022, India and China approved two nasal COVID‑19 vaccines ( iNCOVACC and Convidecia ), which may (as boosters) also reduce transmission (potentially via sterilizing immunity). In December 2022, China approved
20002-592: Was a globally dominant variant that spread to at least 185 countries. It was first discovered in India . Descendant of lineage B.1.617, which also includes the Kappa variant under investigation, it was first discovered in October 2020 and has since spread internationally. On 6 May 2021, British scientists declared B.1.617.2 (which notably lacks mutation at E484Q) as a "variant of concern", labelling it VOC-21APR-02, after they flagged evidence that it spreads more quickly than
20148-586: Was awarded to Katalin Karikó and Drew Weissman for the development of effective mRNA vaccines against COVID-19. Prior to COVID‑19, a vaccine for an infectious disease had never been produced in less than several years – and no vaccine existed for preventing a coronavirus infection in humans. However, vaccines have been produced against several animal diseases caused by coronaviruses, including (as of 2003) infectious bronchitis virus in birds, canine coronavirus , and feline coronavirus . Previous projects to develop vaccines for viruses in
20294-420: Was conducted since week 6, and it confirmed the dominant status of the variant at a rate of 54.1% (week 6) growing to 62.8% (week 9), while the competing Beta variant (lineage B.1.351) was found to be at 18.5% in week 9. In Denmark the variant grew from 0.3% (week 46 of 2020) to become dominant with 65.9% (week 7 of 2021), and it grew further to 92.7% (week 10); with the regional prevalence ranging from 87.3% in
20440-798: Was detected in Tokyo on 6 January 2021 by the National Institute of Infectious Diseases (NIID). It has been labelled as Gamma variant by WHO. The new variant was first identified in four people who arrived in Tokyo having travelled from the Brazilian Amazonas state on 2 January 2021. On 12 January 2021, the Brazil-UK CADDE Centre confirmed 13 local cases of the new Gamma variant in the Amazon rainforest. This variant of SARS-CoV-2 has been named lineage P.1 (although it
20586-678: Was discovered by a team of scientists at COG-UK whose initial results found transmissibility was 70% (50-100%) higher. A study by the Centre for the Mathematical Modelling of Infectious Diseases at the London School of Hygiene & Tropical Medicine reported that the variant was 43 to 90% (range of 95% credible intervals, 38 to 130%) more transmissible than pre-existing variants in the United Kingdom , depending on
20732-610: Was moderately reduced, but it remained detectable in most diagnostic tests. Epsilon (CAL.20C) was first observed in July 2020 by researchers at the Cedars-Sinai Medical Center , California , in one of 1,230 virus samples collected in Los Angeles County since the start of the COVID-19 epidemic . It was not detected again until September when it reappeared among samples in California, but numbers remained very low until November. In November 2020,
20878-425: Was only found nationwide in 0.3% of the positive cases in week 10, and for the region Tyrol - where it had been most prevalent - its share declined from 24.5% in week 4 to just 1.9% in week 10. Regionally Alpha was found to be dominant with over 50% for 7 out of 9 regions , with the only two exceptions being Tyrol and Vorarlberg . In Germany, the largest and probably most representative national survey published by
21024-491: Was previously cleared for Ebola. As multiple COVID‑19 vaccines have been authorized or licensed for use, real-world vaccine effectiveness (RWE) is being assessed using case control and observational studies. A study is investigating the long-lasting protection against SARS-CoV-2 provided by the mRNA vaccines. As of July 2021, at least nine different technology platforms were under research and development to create an effective vaccine against COVID‑19. Most of
21170-542: Was publicly endorsed by NIAID director Anthony Fauci , virologist Jeffery K. Taubenberger , and David M. Morens. In March 2022, the White House released the "National COVID‑19 Preparedness Plan", which recommended accelerating the development of a universal coronavirus vaccine. One attempt at such a vaccine is being developed at the Walter Reed Army Institute of Research . It uses
21316-435: Was shown to be capable of evading 25–61% of inherited immunity from previous coronavirus diseases, leading to the possibility of reinfection after recovery from an earlier COVID-19 infection. As for the fatality ratio, infections by Gamma were also found to be 10–80% more lethal. A study found that people fully vaccinated with Pfizer or Moderna have significantly decreased neutralisation effect against Gamma, although
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