Michelle Roberts: Covid-19: New mutation of Delta variant under close watch in UK. In: bbc.com. BBC, 19. Oktober 2021, abgerufen am 20. Oktober 2021 (englisch): „But in July 2021 experts identified AY.4.2. […] Prof Francois Balloux, director of University College London's Genetics Institute, said: ‚It is potentially a marginally more infectious strain.‘ – ‚It's nothing compared with what we saw with Alpha and Delta, which were something like 50 to 60 percent more transmissible. So we are talking about something quite subtle here and that is currently under investigation.‘ – ‚It is likely to be up to 10 percent more transmissible.‘ – ‚It's good that we are aware. It's excellent that we have the facilities and infrastructure in place to see anything that might be a bit suspicious.‘“
Lineage AY.3. cov-lineages.org, abgerufen am 25. August 2021 (englisch).
Lineage AY.4.2. cov-lineages.org, abgerufen am 21. Oktober 2021 (englisch).
Lineage B.1.617.2. cov-lineages.org, abgerufen am 4. September 2021 (englisch, incl. aller Untervarianten AY.* und deren jeweiliger regionaler Ausbreitung).
Lineage List. cov-lineages.org, abgerufen am 2. April 2022 (englisch).
Mlcochova, P. et al. in Nature: SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion. (PDF; 19,5 MB) nature.com, 6. September 2021, abgerufen am 7. September 2021 (englisch, has been accepted for publication): „B.1.617.2 (Delta) variant was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha). In vitro, B.1.617.2 is 6-fold less sensitive to serum neutralising antibodies from recovered individuals, and 8-fold less sensitive to vaccine-elicited antibodies as compared to wild type (WT) Wuhan-1 bearing D614G. […] Additionally we observed that B.1.617.2 had higher replication and spike mediated entry as compared to B.1.617.1, potentially explaining B.1.617.2 dominance.“doi:10.1038/s41586-021-03944-y, PMID 34488225
Jeromie Wesley Vivian Thangaraj et al. in Journal of Infection: Predominance of delta variant among the COVID-19 vaccinated and unvaccinated individuals, India, May 2021. (PDF; 470 kB) journalofinfection.com, 5. August 2021, abgerufen am 7. September 2021 (englisch, article in press): „India experienced a severe secod wave of SARS-CoV-2 infections during the months of April and May 2021. […] During the course of second wave in India, Delta B.1.617.2 variant emerged as the major sub-lineage among variants that also included B1617.1, B.617.3 and B.1.1.7. […] The study findings indicate that the prevalence of B.1.617.2 was not different between the vaccinated and unvaccinated groups.“doi:10.1016/j.jinf.2021.08.006, PMID 34364949, PMC 8343391 (freier Volltext)
Talha Khan Burki: Lifting of COVID-19 restrictions in the UK and the Delta variant. In: The Lancet. 12. Juli 2021, doi:10.1016/S2213-2600(21)00328-3 (online). Zitat: “The reproductive number (R0) for the original strain of SARS-CoV-2 is roughly 2.5. The Alpha variant (B.1.1.7), which was previously dominant in the UK, is around 60 % more transmissible than the parental virus. The Delta variant is roughly 60 % more transmissible than the Alpha variant, which translates to an R0 of nearly 7.”
Katherine A Twohig et al.: Hospital admission and emergency care attendance risk for SARS-CoV-2 delta (B.1.617.2) compared with alpha (B.1.1.7) variants of concern: a cohort study. In: The Lancet, Infectious Diseases. doi:10.1016/S1473-3099(21)00475-8, PMID 34461056, PMC 8397301 (freier Volltext).
Tzou, P.L. et al., Stanford University: SARS-CoV-2 Variants. Variants genome viewer. In: Coronavirus Antiviral Research Database (CoV-RDB), Resistance Database. stanford.edu, 7. September 2021, abgerufen am 9. September 2021 (englisch, B.1.617.2, Outbreak.info B.1.617.2 Lineage Report).doi:10.3390/v12091006
Yixuan J. Hou et al.: SARS-CoV-2 D614G variant exhibits efficient replication ex vivo and transmission in vivo. In: Science. Band370, Nr.6523, 18. Dezember 2020, S.1464–1468, doi:10.1126/science.abe8499 (englisch, science.org [abgerufen am 6. September 2021]): “The spike aspartic acid–614 to glycine (D614G) substitution […] We engineered a SARS-CoV-2 variant containing this substitution. The variant exhibits more efficient infection, replication, and competitive fitness in primary human airway epithelial cells […] data show that the D614G substitution enhances SARS-CoV-2 infectivity, competitive fitness, and transmission in primary human cells and animal models.”
Theo Dingermann: P681R-Mutation verbessert Fitness der Delta-Variante. In: Medizin/Coronavirus. pharmazeutische-zeitung.de, 16. August 2021, abgerufen am 6. September 2021: „Mutation P681R ganz in der Nähe der Furin-Spaltstelle, die die Untereinheiten Spike 1 (S1) und S2 trennt. […] Delta-P681R-Mutation die Effizienz der Spaltung des Spike-Proteins in S1 und S2 so stark erhöht, dass das Virus nun deutlich besser eine Zelle infizieren kann. […] Während bei der Delta-Variante im Vergleich zum Wildtyp-Virus ein Prolin in ein Arginin umgewandelt ist (P681R), ist bei der Alpha-Variante an der gleichen Stelle ein Prolin in ein Histidin überführt (P681H). Zwar ist die Alpha-Variante ebenfalls fitter als das ursprüngliche Wildtypvirus. Allerdings erweist sich die P681H-Mutation in der Alpha-Variante bei weitem nicht so replikationssteigernd wie die P681R-Mutation in der Delta-Varianten.“ s. a. doi:10.1101/2021.08.12.456173
Delphine Planas et al.: Reduced sensitivity of SARS-CoV-2 variant Delta to antibody neutralization. In: Nature. Vol 596, 8. Juli 2021, S.276–280, doi:10.1038/s41586-021-03777-9, PMID 34237773 (englisch, nature.com [PDF; 6,7MB; abgerufen am 8. September 2021]): “For example, the L452R mutation found in the Delta variant impairs neutralization by antibodies […] Bamlanivimab lost antiviral activity against the Delta variant, in line with previous results that showed that L452R is an escape mutation for this antibody”
Vipul Kumar et al.: Possible Link between Higher Transmissibility of Alpha, Kappa and Delta Variants of SARS-CoV-2 and Increased Structural Stability of Its Spike Protein and hACE2 Affinity. In: MDPI (Hrsg.): International Journal of Molecular Sciences. Band22, Nr.17, 24. August 2021, 9131, doi:10.3390/ijms22179131, PMID 34502041, PMC 8431609 (freier Volltext) – (englisch, mdpi.com [PDF; 3,7MB; abgerufen am 8. September 2021]): “The loss of E484Q mutation and gain of T478K in the B.1.617.2 lineage directly correlated with increase in the positivity rate”
Delphine Planas et al.: Reduced sensitivity of SARS-CoV-2 variant Delta to antibody neutralization. In: Nature. Vol 596, 8. Juli 2021, S.276–280, doi:10.1038/s41586-021-03777-9, PMID 34237773 (englisch, nature.com [PDF; 6,7MB; abgerufen am 8. September 2021]): “The Delta variant was resistant to neutralization by some anti-NTD and anti-RBD monoclonal antibodies […] and these antibodies showed impaired binding to the spike protein. Sera collected from convalescent individuals […] were fourfold less potent against the Delta variant relative to the Alpha […] individuals who had received […] Pfizer or the AstraZeneca vaccine […] Administration of two doses of the vaccine generated a neutralizing response in 95 % of individuals, with titres three- to fivefold lower against the Delta variant than against the Alpha variant. Thus, the spread of the Delta variant is associated with an escape from antibodies […] Whether the absence of E484Q, the presence of T478K or other changes in the spike protein or elsewhere may facilitate viral replication and transmissibility remains unknown. […] The T478K mutation in the RBD is unique to the Delta variant and falls within the epitope region of potent neutralizing monoclonal antibodies categorized as ‘Class 1’. This mutation is close to the E484K mutation that facilitates antibody escape”
Sarah Cherian et al. in microorganisms: SARS-CoV-2 Spike Mutations, L452R, T478K, E484Q and P681R, in the Second Wave of COVID-19 in Maharashtra, India. In: MDPI (Hrsg.): Journals, Microorganisms,. Band9, Nr.7, 20. Juli 2021, 1542, doi:10.3390/microorganisms9071542, PMID 34361977, PMC 8307577 (freier Volltext) – (englisch, mdpi.com [PDF; 2,7MB; abgerufen am 8. September 2021]): “The mutations L452R and E484Q within the RBD were specific to lineage B.1.617.1 and B.1.617.3 while L452R and T478K were specific to lineage B.1.617.2”
Nouara Yahi, Henri Chahinian, Jacques Fantini: Infection-enhancing anti-SARS-CoV-2 antibodies recognize both the original Wuhan/D614G strain and Delta variants. A potential risk for mass vaccination? In: Journal of Infection, 9. August 2021, doi:10.1016/j.jinf.2021.08.010, PDF.
Shabir A. Madhi et al.: Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. In: New England Journal of Medicine. Band384, Nr.20, 2021, ISSN0028-4793, S.1885–1898, doi:10.1056/NEJMoa2102214, PMID 33725432 (englisch).
Michela Antonelli et al.: Risk factors and disease profile of post-vaccination SARS-CoV-2 infection in UK users of the COVID Symptom Study app: a prospective, community-based, nested, case-control study. (PDF) In: Infectious Diseases, Online First. thelancet.com, 1. September 2021, S. 8, 10 f., abgerufen am 10. September 2021 (englisch, s. a. Figure 3: Disease severity and duration factors in SARS-CoV-2-infected vaccinated versus unvaccinated participants, mit zugehörigen Daten in Supplementary Material, S. 7, Supplementary Table 11 & 14. Einzelsymptome dazu s. Supplementary Table 13 & 15): „Almost all symptoms were reported less frequently in infected vaccinated individuals than in infected unvaccinated individuals, and vaccinated participants were more likely to be completely asymptomatic, especially if they were 60 years or older. […] This prospective, community-based, nested, case-control study used data from UK-based […] Data from 1 531 762 app users reporting an RT-PCR or LFAT test […] We found that the odds of having symptoms for 28 days or more after post-vaccination infection were approximately halved by having two vaccine doses. This result suggests that the risk of long COVID is reduced in individuals who have received double vaccination, when additionally considering the already documented reduced risk of infection overall. […] Our data suggest that the risk of post-vaccination SARS-CoV-2 infection is reduced in older age groups. […] Fully vaccinated individuals with COVID-19, especially if they were 60 years or older, were more likely to be completely asymptomatic than were unvaccinated controls. […] Supplementary Table 11. Univariate analysis assessing the probability of asymptomatic infection, severe disease (>5 reported symptoms during acute infection), hospitalisation and duration of symptoms ≥28 days in app participants following first and second vaccination, adjusted by age, BMI, and sex. […] Younger adults (18–59 years); Older adults (60+ years) / Hospitalisation […] D2 […] 0,57 […]; 0,15 / symptoms lasting ≥28 days […] D2 […] 0,37 […]; 0,56 […] D2=After second dose“doi:10.1016/S1473-3099(21)00460-6
Ewen Callaway: Delta coronavirus variant: scientists brace for impact. In: Nature. Nr.595, 1. Juli 2021, S.17f., doi:10.1038/d41586-021-01696-3 (englisch, nature.com [PDF; abgerufen am 4. September 2021]).
ECDC: SARS-CoV-2 variants of concern as of 6 September 2021. In: COVID-19/Situation updates on COVID-19/Variants of concern. ecdc.europa.eu, 6. September 2021, abgerufen am 6. September 2021 (englisch): „Spike mutations of interest: not all spike protein amino acid changes are included – this is not a full reference for assignment of the variants. It includes changes to spike protein residues 319-541 (receptor binding domain) and 613-705 (the S1 part of the S1/S2 junction and a small stretch on the S2 side), and any additional unusual changes specific to the variant. […] Delta B.1.617.2 […] Spike mutations of interest […] L452R, T478K, D614G, P681R“
ECDC: Data on SARS-CoV-2 variants in the EU/EEA. In: COVID-19 / Situation updates on COVID-19 / Download COVID-19 datasets. ecdc.europa.eu, 2. September 2021, abgerufen am 2. September 2021 (englisch, Auswertung: country=Germany, source=GISAID, variant=B.1.617.2, year_week (Kalenderwoche)=18,22,24,26,28 -> Daten: percent_variant).
ECDC: Data on SARS-CoV-2 variants in the EU/EEA. In: COVID-19 / Situation updates on COVID-19 / Download COVID-19 datasets. ecdc.europa.eu, 2. September 2021, abgerufen am 2. September 2021 (englisch, Aktualisierbar: variant=B.1.617.2, source=TESSy, Kalenderwochen: year_week=15 bis 33, country=dargestellte -> Daten: percent_variant).
Jeromie Wesley Vivian Thangaraj et al. in Journal of Infection: Predominance of delta variant among the COVID-19 vaccinated and unvaccinated individuals, India, May 2021. (PDF; 470 kB) journalofinfection.com, 5. August 2021, abgerufen am 7. September 2021 (englisch, article in press): „India experienced a severe secod wave of SARS-CoV-2 infections during the months of April and May 2021. […] During the course of second wave in India, Delta B.1.617.2 variant emerged as the major sub-lineage among variants that also included B1617.1, B.617.3 and B.1.1.7. […] The study findings indicate that the prevalence of B.1.617.2 was not different between the vaccinated and unvaccinated groups.“doi:10.1016/j.jinf.2021.08.006, PMID 34364949, PMC 8343391 (freier Volltext)
Nouara Yahi, Henri Chahinian, Jacques Fantini: Infection-enhancing anti-SARS-CoV-2 antibodies recognize both the original Wuhan/D614G strain and Delta variants. A potential risk for mass vaccination? In: Journal of Infection, 9. August 2021, doi:10.1016/j.jinf.2021.08.010, PDF.
mdpi.com
Vipul Kumar et al.: Possible Link between Higher Transmissibility of Alpha, Kappa and Delta Variants of SARS-CoV-2 and Increased Structural Stability of Its Spike Protein and hACE2 Affinity. In: MDPI (Hrsg.): International Journal of Molecular Sciences. Band22, Nr.17, 24. August 2021, 9131, doi:10.3390/ijms22179131, PMID 34502041, PMC 8431609 (freier Volltext) – (englisch, mdpi.com [PDF; 3,7MB; abgerufen am 8. September 2021]): “The loss of E484Q mutation and gain of T478K in the B.1.617.2 lineage directly correlated with increase in the positivity rate”
Sarah Cherian et al. in microorganisms: SARS-CoV-2 Spike Mutations, L452R, T478K, E484Q and P681R, in the Second Wave of COVID-19 in Maharashtra, India. In: MDPI (Hrsg.): Journals, Microorganisms,. Band9, Nr.7, 20. Juli 2021, 1542, doi:10.3390/microorganisms9071542, PMID 34361977, PMC 8307577 (freier Volltext) – (englisch, mdpi.com [PDF; 2,7MB; abgerufen am 8. September 2021]): “The mutations L452R and E484Q within the RBD were specific to lineage B.1.617.1 and B.1.617.3 while L452R and T478K were specific to lineage B.1.617.2”
Mlcochova, P. et al. in Nature: SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion. (PDF; 19,5 MB) nature.com, 6. September 2021, abgerufen am 7. September 2021 (englisch, has been accepted for publication): „B.1.617.2 (Delta) variant was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha). In vitro, B.1.617.2 is 6-fold less sensitive to serum neutralising antibodies from recovered individuals, and 8-fold less sensitive to vaccine-elicited antibodies as compared to wild type (WT) Wuhan-1 bearing D614G. […] Additionally we observed that B.1.617.2 had higher replication and spike mediated entry as compared to B.1.617.1, potentially explaining B.1.617.2 dominance.“doi:10.1038/s41586-021-03944-y, PMID 34488225
Delphine Planas et al.: Reduced sensitivity of SARS-CoV-2 variant Delta to antibody neutralization. In: Nature. Vol 596, 8. Juli 2021, S.276–280, doi:10.1038/s41586-021-03777-9, PMID 34237773 (englisch, nature.com [PDF; 6,7MB; abgerufen am 8. September 2021]): “For example, the L452R mutation found in the Delta variant impairs neutralization by antibodies […] Bamlanivimab lost antiviral activity against the Delta variant, in line with previous results that showed that L452R is an escape mutation for this antibody”
Delphine Planas et al.: Reduced sensitivity of SARS-CoV-2 variant Delta to antibody neutralization. In: Nature. Vol 596, 8. Juli 2021, S.276–280, doi:10.1038/s41586-021-03777-9, PMID 34237773 (englisch, nature.com [PDF; 6,7MB; abgerufen am 8. September 2021]): “The Delta variant was resistant to neutralization by some anti-NTD and anti-RBD monoclonal antibodies […] and these antibodies showed impaired binding to the spike protein. Sera collected from convalescent individuals […] were fourfold less potent against the Delta variant relative to the Alpha […] individuals who had received […] Pfizer or the AstraZeneca vaccine […] Administration of two doses of the vaccine generated a neutralizing response in 95 % of individuals, with titres three- to fivefold lower against the Delta variant than against the Alpha variant. Thus, the spread of the Delta variant is associated with an escape from antibodies […] Whether the absence of E484Q, the presence of T478K or other changes in the spike protein or elsewhere may facilitate viral replication and transmissibility remains unknown. […] The T478K mutation in the RBD is unique to the Delta variant and falls within the epitope region of potent neutralizing monoclonal antibodies categorized as ‘Class 1’. This mutation is close to the E484K mutation that facilitates antibody escape”
media.nature.com
Ewen Callaway: Delta coronavirus variant: scientists brace for impact. In: Nature. Nr.595, 1. Juli 2021, S.17f., doi:10.1038/d41586-021-01696-3 (englisch, nature.com [PDF; abgerufen am 4. September 2021]).
Mlcochova, P. et al. in Nature: SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion. (PDF; 19,5 MB) nature.com, 6. September 2021, abgerufen am 7. September 2021 (englisch, has been accepted for publication): „B.1.617.2 (Delta) variant was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha). In vitro, B.1.617.2 is 6-fold less sensitive to serum neutralising antibodies from recovered individuals, and 8-fold less sensitive to vaccine-elicited antibodies as compared to wild type (WT) Wuhan-1 bearing D614G. […] Additionally we observed that B.1.617.2 had higher replication and spike mediated entry as compared to B.1.617.1, potentially explaining B.1.617.2 dominance.“doi:10.1038/s41586-021-03944-y, PMID 34488225
Jeromie Wesley Vivian Thangaraj et al. in Journal of Infection: Predominance of delta variant among the COVID-19 vaccinated and unvaccinated individuals, India, May 2021. (PDF; 470 kB) journalofinfection.com, 5. August 2021, abgerufen am 7. September 2021 (englisch, article in press): „India experienced a severe secod wave of SARS-CoV-2 infections during the months of April and May 2021. […] During the course of second wave in India, Delta B.1.617.2 variant emerged as the major sub-lineage among variants that also included B1617.1, B.617.3 and B.1.1.7. […] The study findings indicate that the prevalence of B.1.617.2 was not different between the vaccinated and unvaccinated groups.“doi:10.1016/j.jinf.2021.08.006, PMID 34364949, PMC 8343391 (freier Volltext)
Katherine A Twohig et al.: Hospital admission and emergency care attendance risk for SARS-CoV-2 delta (B.1.617.2) compared with alpha (B.1.1.7) variants of concern: a cohort study. In: The Lancet, Infectious Diseases. doi:10.1016/S1473-3099(21)00475-8, PMID 34461056, PMC 8397301 (freier Volltext).
Delphine Planas et al.: Reduced sensitivity of SARS-CoV-2 variant Delta to antibody neutralization. In: Nature. Vol 596, 8. Juli 2021, S.276–280, doi:10.1038/s41586-021-03777-9, PMID 34237773 (englisch, nature.com [PDF; 6,7MB; abgerufen am 8. September 2021]): “For example, the L452R mutation found in the Delta variant impairs neutralization by antibodies […] Bamlanivimab lost antiviral activity against the Delta variant, in line with previous results that showed that L452R is an escape mutation for this antibody”
Vipul Kumar et al.: Possible Link between Higher Transmissibility of Alpha, Kappa and Delta Variants of SARS-CoV-2 and Increased Structural Stability of Its Spike Protein and hACE2 Affinity. In: MDPI (Hrsg.): International Journal of Molecular Sciences. Band22, Nr.17, 24. August 2021, 9131, doi:10.3390/ijms22179131, PMID 34502041, PMC 8431609 (freier Volltext) – (englisch, mdpi.com [PDF; 3,7MB; abgerufen am 8. September 2021]): “The loss of E484Q mutation and gain of T478K in the B.1.617.2 lineage directly correlated with increase in the positivity rate”
Delphine Planas et al.: Reduced sensitivity of SARS-CoV-2 variant Delta to antibody neutralization. In: Nature. Vol 596, 8. Juli 2021, S.276–280, doi:10.1038/s41586-021-03777-9, PMID 34237773 (englisch, nature.com [PDF; 6,7MB; abgerufen am 8. September 2021]): “The Delta variant was resistant to neutralization by some anti-NTD and anti-RBD monoclonal antibodies […] and these antibodies showed impaired binding to the spike protein. Sera collected from convalescent individuals […] were fourfold less potent against the Delta variant relative to the Alpha […] individuals who had received […] Pfizer or the AstraZeneca vaccine […] Administration of two doses of the vaccine generated a neutralizing response in 95 % of individuals, with titres three- to fivefold lower against the Delta variant than against the Alpha variant. Thus, the spread of the Delta variant is associated with an escape from antibodies […] Whether the absence of E484Q, the presence of T478K or other changes in the spike protein or elsewhere may facilitate viral replication and transmissibility remains unknown. […] The T478K mutation in the RBD is unique to the Delta variant and falls within the epitope region of potent neutralizing monoclonal antibodies categorized as ‘Class 1’. This mutation is close to the E484K mutation that facilitates antibody escape”
Sarah Cherian et al. in microorganisms: SARS-CoV-2 Spike Mutations, L452R, T478K, E484Q and P681R, in the Second Wave of COVID-19 in Maharashtra, India. In: MDPI (Hrsg.): Journals, Microorganisms,. Band9, Nr.7, 20. Juli 2021, 1542, doi:10.3390/microorganisms9071542, PMID 34361977, PMC 8307577 (freier Volltext) – (englisch, mdpi.com [PDF; 2,7MB; abgerufen am 8. September 2021]): “The mutations L452R and E484Q within the RBD were specific to lineage B.1.617.1 and B.1.617.3 while L452R and T478K were specific to lineage B.1.617.2”
Shabir A. Madhi et al.: Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. In: New England Journal of Medicine. Band384, Nr.20, 2021, ISSN0028-4793, S.1885–1898, doi:10.1056/NEJMoa2102214, PMID 33725432 (englisch).
United Kingdom Variant Report. outbreak.info, abgerufen am 26. Oktober 2021 (englisch, mit explizitem Diagramm zur Verbreitung von AY.4.2 in Großbritannien).
AY.3 Lineage Report. In: Lineage/Mutation Tracker. outbreak.info, 25. August 2021, abgerufen am 28. August 2021 (englisch).
pango.network
New AY lineages and an update to AY.4-AY.12. In: New lineages. pango.network, 27. August 2021, abgerufen am 8. September 2021 (englisch, s. a. Table of currently designated AY lineages, their predominant geographical location(s) and their associated mutation(s).): „includes new lineages AY.13-AY.25 and an update to the previously designated AY.4-AY.12 lineages. […] does not imply any functional biological difference from B.1.617.2 and, like B.1.617.2, they correspond to the WHO-defined Delta variant […] table at the bottom of this article shows the countries and mutations that are associated with each of the AY lineages. […] This means that a number of virus genomes that were previously designated B.1.617.2 are now designated to one of the AY lineages […] We expect that more AY lineages will continue to follow.“
New AY lineages. In: New lineages. pango.network, 13. August 2021, abgerufen am 4. September 2021 (englisch): „their designation doesn’t imply any functional biological difference from B.1.617.2. […] The AY lineages break up B.1.617.2 into smaller related clusters that can be tracked separately. Each of these clusters is usually associated with a significant epidemiological event (for example, introduction into a new country with onward transmission) and will let researchers build a more fine-grained picture of how Delta variant is circulating nationally, and around the world.“
Summary of designated AY lineages. In: New lineages. pango.network, 1. November 2021, abgerufen am 11. November 2021 (englisch, Table of currently designated AY lineages, their predominant geographical location(s) and their associated mutation(s)): „Their designation does not imply any functional biological difference from B.1.617.2 and, like B.1.617.2, they correspond to the WHO-defined Delta variant“
pharmazeutische-zeitung.de
Theo Dingermann: P681R-Mutation verbessert Fitness der Delta-Variante. In: Medizin/Coronavirus. pharmazeutische-zeitung.de, 16. August 2021, abgerufen am 6. September 2021: „Mutation P681R ganz in der Nähe der Furin-Spaltstelle, die die Untereinheiten Spike 1 (S1) und S2 trennt. […] Delta-P681R-Mutation die Effizienz der Spaltung des Spike-Proteins in S1 und S2 so stark erhöht, dass das Virus nun deutlich besser eine Zelle infizieren kann. […] Während bei der Delta-Variante im Vergleich zum Wildtyp-Virus ein Prolin in ein Arginin umgewandelt ist (P681R), ist bei der Alpha-Variante an der gleichen Stelle ein Prolin in ein Histidin überführt (P681H). Zwar ist die Alpha-Variante ebenfalls fitter als das ursprüngliche Wildtypvirus. Allerdings erweist sich die P681H-Mutation in der Alpha-Variante bei weitem nicht so replikationssteigernd wie die P681R-Mutation in der Delta-Varianten.“ s. a. doi:10.1101/2021.08.12.456173
Coronavirus: Wohl höhere Pathogenität bei Delta-Variante. In: Pharmazeutische Zeitung. 5. Juni 2021, abgerufen am 8. Juni 2021 („Die Delta-Variante des Coronavirus (B.1.617.2) ist vermutlich nicht nur deutlich ansteckender, sondern auch pathogener als andere Varianten und führt häufiger zu Hospitalisierungen. Das meldet die englische Gesundheitsbehörde. Offenbar kann die Variante auch Teilimmunisierte infizieren.“ → Quelle: ebenda).
publishing.service.gov.uk
assets.publishing.service.gov.uk
SARS-CoV-2 variants of concern and variants under investigation in England – Technical briefing 25. (PDF; 4,5 MB) In: Coronavirus (COVID-19). gov.uk, UK Health Security Agency, 15. Oktober 2021, S. 22, abgerufen am 20. Oktober 2021 (englisch): „One recently designated sublineage, AY.4.2, is not yet assigned by the Pangolin tool […]. This sublineage is currently increasing in frequency. It includes spike mutations A222V and Y145H. In the week beginning 27 September 2021 (the last week with complete sequencing data), this sublineage accounted for approximately 6% of all sequences generated, on an increasing trajectory. This estimate may be imprecise due to known sequencing issues affecting position S:145. Further assessment is underway.“
SARS-CoV-2 variants of concern and variants under investigation in England – Technical briefing 27. (PDF; 9,4 MB) In: Coronavirus (COVID-19). gov.uk, UK Health Security Agency, 29. Oktober 2021, S. 47–60; hier: S. 47 f., 50, 57, 59, abgerufen am 3. November 2021 (englisch): „After adjustment for the potential confounding variables there was no evidence that AY4.2 differed significantly compared to non-AY4.2 Delta cases, both symptomatic and asymptomatic, across the 3 vaccines in circulation. […] These initial analyses produced overlapping confidence intervals between rates of hospitalisation or death among VUI-21OCT-01 and Delta, suggesting that rates are similar and differences observed are not statistically significant. However, these crude analyses do not adjust for crucial factors that can influence outcomes such as age and vaccination status and should be interpreted with caution. […] Growth rate is context dependent and cannot be interpreted as a change in biological transmissibility. […] Secondary attack rate for household contacts of cases with VUI-21OCT-01 was 12.2% (95% CI: 11.8% - 12.7%), higher than that observed for other Delta cases where it was 11.2% (95% CI: 11.1% - 11.3%). In non-household settings, the secondary attack rate was higher for VUI-21OCT-01 than other Delta cases, but this difference was not significant.“
Elena Lynch: Deltakron: Die neue Virusvariante könnte bald auch in der Schweiz auftreten. In: nzz.ch. 21. März 2022, archiviert vom Original am 21. März 2022; abgerufen am 21. März 2022: „Richard Neher ist Biophysiker am Bioinstitut der Universität Basel sowie Mitglied der Science-Task-Force und […] findet, Deltakron sei eine ‹ungünstige umgangssprachliche Bezeichnung›. Das französische Forschungszentrum Institut Pasteur nannte die Variante in seiner Untersuchung ‹Deltamikron›. […] Neher empfiehlt sie ‹Rekombinante› zu nennen.“
ECDC: Data on SARS-CoV-2 variants in the EU/EEA. In: COVID-19 / Situation updates on COVID-19 / Download COVID-19 datasets. ecdc.europa.eu, 3. März 2022, archiviert vom Original am 6. März 2022; abgerufen am 6. März 2022 (englisch, ‚Dataset 3 Mar 2022‘ / Aktualisierbar: country=Germany, source=GISAID, variant B.1.617.2 -> Daten: percent_variant).
Yixuan J. Hou et al.: SARS-CoV-2 D614G variant exhibits efficient replication ex vivo and transmission in vivo. In: Science. Band370, Nr.6523, 18. Dezember 2020, S.1464–1468, doi:10.1126/science.abe8499 (englisch, science.org [abgerufen am 6. September 2021]): “The spike aspartic acid–614 to glycine (D614G) substitution […] We engineered a SARS-CoV-2 variant containing this substitution. The variant exhibits more efficient infection, replication, and competitive fitness in primary human airway epithelial cells […] data show that the D614G substitution enhances SARS-CoV-2 infectivity, competitive fitness, and transmission in primary human cells and animal models.”
Talha Khan Burki: Lifting of COVID-19 restrictions in the UK and the Delta variant. In: The Lancet. 12. Juli 2021, doi:10.1016/S2213-2600(21)00328-3 (online). Zitat: “The reproductive number (R0) for the original strain of SARS-CoV-2 is roughly 2.5. The Alpha variant (B.1.1.7), which was previously dominant in the UK, is around 60 % more transmissible than the parental virus. The Delta variant is roughly 60 % more transmissible than the Alpha variant, which translates to an R0 of nearly 7.”
Michela Antonelli et al.: Risk factors and disease profile of post-vaccination SARS-CoV-2 infection in UK users of the COVID Symptom Study app: a prospective, community-based, nested, case-control study. (PDF) In: Infectious Diseases, Online First. thelancet.com, 1. September 2021, S. 8, 10 f., abgerufen am 10. September 2021 (englisch, s. a. Figure 3: Disease severity and duration factors in SARS-CoV-2-infected vaccinated versus unvaccinated participants, mit zugehörigen Daten in Supplementary Material, S. 7, Supplementary Table 11 & 14. Einzelsymptome dazu s. Supplementary Table 13 & 15): „Almost all symptoms were reported less frequently in infected vaccinated individuals than in infected unvaccinated individuals, and vaccinated participants were more likely to be completely asymptomatic, especially if they were 60 years or older. […] This prospective, community-based, nested, case-control study used data from UK-based […] Data from 1 531 762 app users reporting an RT-PCR or LFAT test […] We found that the odds of having symptoms for 28 days or more after post-vaccination infection were approximately halved by having two vaccine doses. This result suggests that the risk of long COVID is reduced in individuals who have received double vaccination, when additionally considering the already documented reduced risk of infection overall. […] Our data suggest that the risk of post-vaccination SARS-CoV-2 infection is reduced in older age groups. […] Fully vaccinated individuals with COVID-19, especially if they were 60 years or older, were more likely to be completely asymptomatic than were unvaccinated controls. […] Supplementary Table 11. Univariate analysis assessing the probability of asymptomatic infection, severe disease (>5 reported symptoms during acute infection), hospitalisation and duration of symptoms ≥28 days in app participants following first and second vaccination, adjusted by age, BMI, and sex. […] Younger adults (18–59 years); Older adults (60+ years) / Hospitalisation […] D2 […] 0,57 […]; 0,15 / symptoms lasting ≥28 days […] D2 […] 0,37 […]; 0,56 […] D2=After second dose“doi:10.1016/S1473-3099(21)00460-6
Elena Lynch: Deltakron: Die neue Virusvariante könnte bald auch in der Schweiz auftreten. In: nzz.ch. 21. März 2022, archiviert vom Original am 21. März 2022; abgerufen am 21. März 2022: „Richard Neher ist Biophysiker am Bioinstitut der Universität Basel sowie Mitglied der Science-Task-Force und […] findet, Deltakron sei eine ‹ungünstige umgangssprachliche Bezeichnung›. Das französische Forschungszentrum Institut Pasteur nannte die Variante in seiner Untersuchung ‹Deltamikron›. […] Neher empfiehlt sie ‹Rekombinante› zu nennen.“
ECDC: Data on SARS-CoV-2 variants in the EU/EEA. In: COVID-19 / Situation updates on COVID-19 / Download COVID-19 datasets. ecdc.europa.eu, 3. März 2022, archiviert vom Original am 6. März 2022; abgerufen am 6. März 2022 (englisch, ‚Dataset 3 Mar 2022‘ / Aktualisierbar: country=Germany, source=GISAID, variant B.1.617.2 -> Daten: percent_variant).
WHO: WHO Director-General's opening remarks at the 8th meeting of the IHR Emergency Committee on COVID-19 – 14 July 2021. who.int, 14. Juli 2021, abgerufen am 6. September 2021 (englisch): „The Delta variant is now in more than 111 countries and we expect it to soon be the dominant COVID-19 strain circulating worldwide, if it isn’t already. The Delta variant is one of the main drivers of the current increase in transmission, fuelled by increased social mixing and mobility, and inconsistent use of proven public health and social measures. At the same time, we continue to see a shocking disparity in the global distribution of vaccines, and unequal access to life-saving tools.“
Weekly epidemiological update on COVID-19 - 20 July 2021. who.int, 20. Juli 2021, S. 6, abgerufen am 6. August 2021 (englisch): „A recent study from China during an outbreak of the Delta variant examined the time interval from the exposure of a quarantined population to the first positive PCR result and found that the interval may be shorter for the Delta variant when compared to non-VOCs [4 (IQR 3.00-5.00) days compared to 6 (IQR 5.00 to 8.00) days, respectively]. Moreover, the viral load of the first positive test of Delta infection was over 1200 times higher than non-VOCs, suggesting that this VOC may be able to replicate faster and be more infectious during the early stages of infection.“
WHO: COVID-19 Weekly Epidemiological Update Edition 39. (PDF) Data as received by WHO from national authorities, as of 9 May 2021. who.int, 9. Mai 2021, S. 4 f., abgerufen am 5. September 2021 (englisch): „B.1.617.2 […] Number of lineage-defining spike mutations* […] 8 […] Characteristic spike mutations* […] T19R, G142D, del157/158, L452R, T478K, D614G, P681R, D950N […] *Mutations found in >60% of sequences […] A structural analysis of B.1.617 receptor binding domain (RBD) mutations (L452R and E484Q, along with P681R in the furin cleavage site) suggest that mutations in these variants may result in increased ACE2 binding and rate of S1-S2 cleavage resulting in better transmissibility, and possibly capacity to escape binding and neutralization by some monoclonal antibodies.“
Shabir A. Madhi et al.: Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. In: New England Journal of Medicine. Band384, Nr.20, 2021, ISSN0028-4793, S.1885–1898, doi:10.1056/NEJMoa2102214, PMID 33725432 (englisch).
