- New algorithm predicts those most at risk of serious Covid-19 outcomes from 14 or more days after second vaccination dose, when substantial immunity is expected to have developed
- Authors hope this new risk tool will allow those who perceive risk to be high to make more informed decisions regarding shielding and potentially inform policy and clinical decisions on booster vaccine doses and monoclonal antibodies
In a paper published in the British Medical Journal, they write that by updating the QCovid tool developed in 2020, which directly influenced UK policy in February 2021, adding 1.5 million people in February 2021 to list of those advised to shield, they are able to identify groups more at risk of hospitalisation or death from Covid-19.
They used national linked datasets from general practice, national immunisation and SARS-CoV-2 testing, death registry and hospital episode data, in order to analyse a sample of over 6.9m vaccinated adults, of whom 5.2m had both vaccines doses, which was representative of the UK population as a whole. This sample included 2,031 Covid-19 deaths and 1,929 Covid-19 related hospital admissions, of which 81 deaths and 71 admissions occurred 14 or more days after the second vaccine dose.