The omicron (B. 1.1. 529) variant, first detected in the UK on Nov 27, 2021, rapidly became
the dominant strain, due in part to reduced vaccine effectiveness. 1 An increase in …

The Omicron sub-lineages BA. 4 and BA. 5, identified in South Africa in early 2022, 1 were
first detected in England in April 2022. 2 A case surge followed despite England having …

Correspondence 1664 www. thelancet. com/infection Vol 22 December 2022 emergency
department encounters only in the first 3 months after a third dose of vaccine (table). At 6 …

In the UK, COVID-19 vaccination for adults began in December, 2020. 1 Because children
and adolescents have a low risk of severe COVID-19 and due to concerns about rare but …

Background A rapid increase in coronavirus disease 2019 (Covid-19) cases due to the
omicron (B. 1.1. 529) variant of severe acute respiratory syndrome coronavirus 2 in highly …

Background Bivalent BA. 1 booster vaccines were offered to adults aged 50 years or older
and clinically vulnerable people as part of the 2022 autumn COVID-19 booster vaccination …

The SARS-CoV-2 omicron (B. 1.1. 529) variant has rapidly become globally dominant,
displacing the previously dominant delta (B1. 617.2) variant. The viral spike (S) protein is the …

Background A rapid increase in cases due to the SARS-CoV-2 Omicron (B. 1.1. 529) variant
in highly vaccinated populations has raised concerns about the effectiveness of current …

Booster vaccination with messenger RNA (mRNA) vaccines has been offered to adults in
England starting on 14 September 2021. We used a test-negative case–control design to …

Background With large waves of infection driven by the B. 1.1. 529 (omicron) variant of
severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), alongside evidence of …