Older people, men and those from ethnic backgrounds are more likely to end up in hospital or die even after they have been double-vaccinated against Covid-19, researchers say.
Scientists used a range of data to show that while the risk of severe Covid-19 after vaccination remains low, some people are at greater risk than others.
Also at greater risk are those from a deprived background, the immunosuppressed, residents in care homes, and people with chronic conditions such as Down’s syndrome, kidney disease, sickle cell disease, HIV/Aids and liver cirrhosis.
University of Oxford >
A tool developed by researchers predicts those most at risk of serious Covid-19 outcomes from 14 or more days after a second vaccination dose, when substantial immunity is expected to have developed.
They hope it will help patients work with their doctors to make decisions about continued shielding, and will help inform policy around booster jabs and Covid treatments.
University of Oxford scientists used national datasets from GP surgeries, immunisation and Covid testing, as well as deaths and hospital admission data.
A sample of more than 6.9 million vaccinated adults was analysed, of whom 5.2 million had had both doses – representative of the UK population as a whole.
The sample included 2,031 Covid-19 deaths and 1,929 Covid-related hospital admissions, of which 81 deaths and 71 admissions occurred 14 or more days after a second vaccine dose.
Based on this, the researchers calculated risk by measures including age, sex, ethnic group and the background rate of Covid infections.
Commenting on why other ethnic groups may have lower risk, Professor Aziz Sheikh, of the University of Edinburgh and a co-author of the paper, said it may be due to social reasons.
He said: “I think the fact that some of the ethnic variations are diminishing suggests that a lot of this was because it’s socially patterned – perhaps because of occupational risk considerations etc.
“I think with the two subgroups that remain, this is speculative, but these groups – the Indians and Pakistanis – do tend to have slightly higher household sizes and so there may be that kind of within household transmission going on.”
According to the paper, published in the British Medical Journal, researchers did not distinguish between the type of vaccination offered.
The study may have also been limited by factors such as exposure to Covid, as background information such as occupation is not often recorded in general practice or hospital records.