We welcome the Correspondence from Westyn Branch-Elliman and Paul A Monach in which they hypothesise that there are some individuals who, after completion of their primary COVID-19 vaccination course, do not need frequent vaccine re-dosing; others who might benefit from periodic re-dosing; and others who could, irrespective of the number of doses given, respond poorly to vaccines.1
Specifically, we support their suggestion of potential follow-up analyses of UK datasets2 of severe COVID-19 outcomes after full vaccination and initial booster vaccines to investigate this hypothesis. An approach to tackle these analyses could be to develop a risk prediction model for severe COVID-19 outcomes (ie, COVID-19 hospitalisation or death), similar to the QCOVID model at the request of the UK's Chief Medical Officers.3 This prediction model could help identify individuals at both very low risk and high risk of a severe COVID-19 outcome. With such a model, we could then explore if the individuals in the high-risk group are likely to benefit from either frequent vaccine re-dosing or the growing array of COVID-19 therapeutics. We are currently in the process of conducting a UK-wide analysis to investigate the factors associated with increased risk of severe COVID-19 outcomes among individuals in the UK who received a vaccine as part of the 2022 COVID-19 autumn booster campaign and who might also have received treatments with monoclonal antibodies or antivirals.4
There is also the opportunity to use the Scotland-wide Early Pandemic Evaluation and Enhanced Surveillance of COVID-19 (EAVE II) platform, which is uniquely placed within the UK, because towards the end of 2022 it had linked serology data to the existing electronic health record and vaccination data, to enable identification of serological responses to vaccination.5
Acknowledgments
AS and CR are members of the Scottish Government Chief Medical Officer's COVID-19 Advisory Group. AS is a member of the Scottish Government's Standing Committee on Pandemic Preparedness, the UK Government's New and Emerging Respiratory Virus Threats Advisory Group (known as NERVTAG) Risk Stratification Subgroup, the UK Department of Health and Social Care's COVID-19 Therapeutics Modelling Group, and was a member of AstraZeneca's COVID-19 strategic thrombocytopenia taskforce. All of AS's roles are unfunded. CR is a member of the Scientific Pandemic Influenza Group on Modelling, Medicines and Healthcare products Regulatory Agency Vaccine Benefit and Risk Working Group. UA declares no competing interests.
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