Effect of second booster vaccinations and prior infection against SARS-CoV-2 in the UK SIREN healthcare worker cohort

Peter D. Kirwan*, Victoria J. Hall, Sarah Foulkes, Ashley D. Otter, Katie Munro, Dominic Sparkes, Anna Howells, Naomi Platt, Jonathan Broad, David Crossman, Chris Norman, Diane Corrigan, Christopher H. Jackson, Michelle Cole, Colin S. Brown, Ana Atti, Jasmin Islam, SIREN Study Group, Melanie Dembinsky, David GoldbergLynne Haahr, Annelysse Jorgenson, Ayodeji Matuluko, Desy Nuryunarsih, Lesley Price, Nicole Sergenson, Sally Stewart, Anne M. Presanis, Andre Charlett, Daniela De Angelis, Susan Hopkins

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)
9 Downloads (Pure)

Abstract

BACKGROUND: The protection of fourth dose mRNA vaccination against SARS-CoV-2 is relevant to current global policy decisions regarding ongoing booster roll-out. We aimed to estimate the effect of fourth dose vaccination, prior infection, and duration of PCR positivity in a highly-vaccinated and largely prior-COVID-19 infected cohort of UK healthcare workers.

METHODS: Participants underwent fortnightly PCR and regular antibody testing for SARS-CoV-2 and completed symptoms questionnaires. A multi-state model was used to estimate vaccine effectiveness (VE) against infection from a fourth dose compared to a waned third dose, with protection from prior infection and duration of PCR positivity jointly estimated.

FINDINGS: 1298 infections were detected among 9560 individuals under active follow-up between September 2022 and March 2023. Compared to a waned third dose, fourth dose VE was 13.1% (95% CI 0.9 to 23.8) overall; 24.0% (95% CI 8.5 to 36.8) in the first 2 months post-vaccination, reducing to 10.3% (95% CI -11.4 to 27.8) and 1.7% (95% CI -17.0 to 17.4) at 2-4 and 4-6 months, respectively. Relative to an infection >2 years ago and controlling for vaccination, 63.6% (95% CI 46.9 to 75.0) and 29.1% (95% CI 3.8 to 43.1) greater protection against infection was estimated for an infection within the past 0-6, and 6-12 months, respectively. A fourth dose was associated with greater protection against asymptomatic infection than symptomatic infection, whilst prior infection independently provided more protection against symptomatic infection, particularly if the infection had occurred within the previous 6 months. Duration of PCR positivity was significantly lower for asymptomatic compared to symptomatic infection.

INTERPRETATION: Despite rapid waning of protection, vaccine boosters remain an important tool in responding to the dynamic COVID-19 landscape; boosting population immunity in advance of periods of anticipated pressure, such as surging infection rates or emerging variants of concern.

FUNDING: UK Health Security Agency, Medical Research Council, NIHR HPRU Oxford, Bristol, and others.

Original languageEnglish
Article number100809
Number of pages12
JournalThe Lancet Regional Health - Europe
Volume36
Early online date14 Dec 2023
DOIs
Publication statusPublished - Jan 2024

Keywords

  • Asymptomatic
  • Cohort study
  • Healthcare worker
  • SARS-CoV-2
  • Symptomatic
  • Vaccine effectiveness

ASJC Scopus subject areas

  • Internal Medicine
  • Oncology
  • Health Policy

Fingerprint

Dive into the research topics of 'Effect of second booster vaccinations and prior infection against SARS-CoV-2 in the UK SIREN healthcare worker cohort'. Together they form a unique fingerprint.

Cite this