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Several factors may account for the recent increased spread of the SARS-CoV-2 Delta sub-lineage AY.4.2 in the United Kingdom, Romania, Poland, and Denmark. We evaluated the sensitivity of AY.4.2 to neutralisation by sera from 30 Comirnaty (BNT162b2 mRNA) vaccine recipients in Denmark in November 2021. AY.4.2 neutralisation was comparable to other circulating Delta lineages or sub-lineages. Conversely, the less prevalent B.1.617.2 with E484K showed a significant more than 4-fold reduction in neutralisation that warrants surveillance of strains with the acquired E484K mutation.


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  1. United Kingdom Health Security Agency (UKHSA). SARS-CoV-2 variants of concern and variants under investigation in England. Technical Briefing 26. London: UKHSA; 2021. Available from: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1028113/Technical_Briefing_26.pdf
  2. United Kingdom Health Security Agency (UKHSA). SARS-CoV-2 variants of concern and variants under investigation in England. Technical Briefing 29. London: UKHSA; 2021. Available from: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1036501/Technical_Briefing_29_published_26_November_2021.pdf
  3. World Health Organization (WHO). COVID-19 Weekly Epidemiological Update - edition 63. Geneva: WHO; 2021. Available from: https://apps.who.int/iris/handle/10665/347449
  4. Latif AA, Mullen JL, Alkuzweny M, Tsueng G, Cano M, Haag E, et al. AY.4.2 Lineage Report. Outbreak.info. [Accessed: 26 Nov 2021]. Available from: https://outbreak.info/situation-reports?pango=AY.4.2&loc=IND&loc=GBR&loc=USA&selected
  5. Chen RE, Zhang X, Case JB, Winkler ES, Liu Y, VanBlargan LA, et al. Resistance of SARS-CoV-2 variants to neutralization by monoclonal and serum-derived polyclonal antibodies. Nat Med. 2021;27(4):717-26.  https://doi.org/10.1038/s41591-021-01294-w  PMID: 33664494 
  6. Liu Z, VanBlargan LA, Bloyet L-M, Rothlauf PW, Chen RE, Stumpf S, et al. Identification of SARS-CoV-2 spike mutations that attenuate monoclonal and serum antibody neutralization. Cell Host Microbe. 2021;29(3):477-488.e4.  https://doi.org/10.1016/j.chom.2021.01.014  PMID: 33535027 
  7. United Kingdom Health Security Agency (UKHSA). SARS-CoV-2 variants of concern and variants under investigation in England. Technical Briefing 27. London: UKHSA; 2021. Available from: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1029715/technical-briefing-27.pdf
  8. Baj A, Novazzi F, Pasciuta R, Genoni A, Ferrante FD, Valli M, et al. Breakthrough infections of E484K-harboring SARS-CoV-2 Delta variant, Lombardy, Italy. Emerg Infect Dis. 2021;27(12):3180-2.  https://doi.org/10.3201/eid2712.211792  PMID: 34499599 
  9. Polack FP, Thomas SJ, Kitchin N, Absalon J, Gurtman A, Lockhart S, et al. Safety and efficacy of the BNT162b2 mRNA Covid-19 vaccine. N Engl J Med. 2020;383(27):2603-15.  https://doi.org/10.1056/NEJMoa2034577  PMID: 33301246 
  10. GeurtsvanKessel CH, Okba NMA, Igloi Z, Bogers S, Embregts CWE, Laksono BM, et al. An evaluation of COVID-19 serological assays informs future diagnostics and exposure assessment. Nat Commun. 2020;11(1):3436.  https://doi.org/10.1038/s41467-020-17317-y  PMID: 32632160 
  11. Lassaunière R, Frische A, Harboe ZB, Nielsen ACY, Fomsgaard A, Krogfelt KA, et al. Evaluation of nine commercial SARS-CoV-2 immunoassays. medRxiv. 2020:2020.04.09.20056325. Preprint. 10.1101/2020.04.09.20056325
  12. World Health Organization (WHO). Manual for the laboratory diagnosis and virological surveillance of influenza. Geneva: WHO; 2011. Available from: https://apps.who.int/iris/handle/10665/44518
  13. Nguyen D, Simmonds P, Steenhuis M, Wouters E, Desmecht D, Garigliany M, et al. SARS-CoV-2 neutralising antibody testing in Europe: towards harmonisation of neutralising antibody titres for better use of convalescent plasma and comparability of trial data. Euro Surveill. 2021;26(27):2100568.  https://doi.org/10.2807/1560-7917.ES.2021.26.27.2100568  PMID: 34240697 
  14. Hodcroft EB, Zuber M, Nadeau S, Vaughan TG, Crawford KHD, Althaus CL, et al. Spread of a SARS-CoV-2 variant through Europe in the summer of 2020. Nature. 2021;595(7869):707-12.  https://doi.org/10.1038/s41586-021-03677-y  PMID: 34098568 
  15. Latif AA, Mullen JL, Alkuzweny M, Tsueng G, Cano M, Haag E, et al. S:E484K Mutation Report. Outbreak.info. [Accessed: 10 Nov 2021]. Available at: https://outbreak.info/situation-reports?pango&muts=S%3AE484K
  16. Jangra S, Ye C, Rathnasinghe R, Stadlbauer D, Krammer F, Simon V, et al. SARS-CoV-2 spike E484K mutation reduces antibody neutralisation. Lancet Microbe. 2021;2(7):e283-4.  https://doi.org/10.1016/S2666-5247(21)00068-9  PMID: 33846703 
  17. Wang P, Nair MS, Liu L, Iketani S, Luo Y, Guo Y, et al. Antibody resistance of SARS-CoV-2 variants B.1.351 and B.1.1.7. Nature. 2021;593(7857):130-5.  https://doi.org/10.1038/s41586-021-03398-2  PMID: 33684923 
  18. Github.com. Issue # 361. Proposal to split B.1.1.529 to incorporate a newly characterised sibling lineage. GitHub Repository. GitHub. [Accessed: 8 Dec 2021]. Available from: https://github.com/cov-lineages/pango-designation/issues/361

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