The Lancet Regional Health. Europe (Feb 2023)

Effectiveness of BNT162b2 COVID-19 vaccination in prevention of hospitalisations and severe disease in adults with SARS-CoV-2 Delta (B.1.617.2) and Omicron (B.1.1.529) variant between June 2021 and July 2022: A prospective test negative case–control studyResearch in context

  • Anastasia Chatzilena,
  • Catherine Hyams,
  • Rob Challen,
  • Robin Marlow,
  • Jade King,
  • David Adegbite,
  • Jane Kinney,
  • Madeleine Clout,
  • Nick Maskell,
  • Jennifer Oliver,
  • Leon Danon,
  • Adam Finn,
  • Anna Morley,
  • Amelia Langdon,
  • Anabella Turner,
  • Anya Mattocks,
  • Bethany Osborne,
  • Charli Grimes,
  • Claire Mitchell,
  • Emma Bridgeman,
  • Emma Scott,
  • Fiona Perkins,
  • Francesca Bayley,
  • Gabriella Ruffino,
  • Gabriella Valentine,
  • Grace Tilzey,
  • Johanna Kellett Wright,
  • Julia Brzezinska,
  • Julie Cloake,
  • Katarina Milutinovic,
  • Kate Helliker,
  • Katie Maughan,
  • Kazminder Fox,
  • Konstantina Minou,
  • Lana Ward,
  • Leah Fleming,
  • Leigh Morrison,
  • Lily Smart,
  • Louise Wright,
  • Lucy Grimwood,
  • Maddalena Bellavia,
  • Marianne Vasquez,
  • Maria Garcia Gonzalez,
  • Milo Jeenes-Flanagan,
  • Natalie Chang,
  • Niall Grace,
  • Nicola Manning,
  • Oliver Griffiths,
  • Pip Croxford,
  • Peter Sequenza,
  • Rajeka Lazarus,
  • Rhian Walters,
  • Robin Marlow,
  • Robyn Heath,
  • Rupert Antico,
  • Sandi Nammuni Arachchge,
  • Seevakumar Suppiah,
  • Taslima Mona,
  • Tawassal Riaz,
  • Vicki Mackay,
  • Zandile Maseko,
  • Zoe Taylor,
  • Zsolt Friedrich,
  • Zsuzsa Szasz-Benczur

Journal volume & issue
Vol. 25
p. 100552

Abstract

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Summary: Background: Whilst other studies have reported the effectiveness of mRNA vaccination against hospitalisation, including emergency department or intensive care admission, few have assessed effectiveness against other more clinically robust indices of COVID-19 severity. Methods: A prospective single-centre test-negative design case–control study of adults hospitalised with COVID-19 disease or other acute respiratory disease between 1 June 2021 and 20 July 2022. We assessed VE (vaccine effectiveness) against hospitalisation, length of stay [LOS] >3 days, WHO COVID Score >5 and supplementary oxygen FiO2 (fraction inspired oxygen) >28%, conducting regression analyses controlling for age, gender, index of multiple deprivation, Charlson comorbidity index, time, and community infection prevalence. Findings: 935 controls and 546 cases were hospitalised during the Delta period, with 721 controls and 372 cases hospitalised during the Omicron study period. Two-dose BNT162b2 was associated with VE 82.5% [95% confidence interval 76.2%–87.2%] against hospitalisation following Delta infection, 63.3% [26.9–81.8%], 58.5% [24.8–77.3%], and 51.5% [16.7–72.1%] against LOS >3 days, WHO COVID Score >5, and requirement for FiO2 >28% respectively. Three-dose BNT162b2 protection against hospitalisation with Omicron infection was 30.9% [5.9–49.3%], with sensitivity analyses ranging from 28.8–72.6%. Protection against LOS >3 days, WHO COVID Score >5 and requirement for FiO2 >28% was 56.1% [20.6–76.5%], 58.8% [31.2–75.8%], and 41.5% [−0.4–66.3%], respectively. In the UK, BNT162b2 was prioritised for high-risk individuals and those aged >75 years. In the latter group we found a higher estimate of VE against hospitalisation of 47.2% [16.8–66.6%]. Interpretation: BNT162b2 vaccination results in risk reductions for hospitalisation and multiple patient outcomes following Delta and Omicron COVID-19 infection, particularly in older adults. BNT162b2 remains effective against severe SARS-CoV-2 disease. Funding: AvonCAP is an investigator-led project funded under a collaborative agreement by Pfizer.

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