Vaccination is proving highly effective in preventing deaths and infection in the UK, according to a series of studies released as lockdown restrictions are relaxed in England.
The UK government said 30 million people have now received vaccines.
Vaccination against COVID-19 has already prevented more than 6,000 deaths in the elderly population, according to one new analysis.
Public Health England estimated the figure by modelling the number of deaths that would have been expected until the end of February.
Its calculations correlate death rates with the anticipated point of vaccine effectiveness, 31 days after vaccination.
It was able to link vaccination to 5,900 deaths prevented in those over the age of 800 and 200 among the over 70s.
A separate analysis by Warwick University concluded that 6,600 deaths in all age groups were prevented until the end of February – as vaccination countered the effect of the new variants of the virus in extending the third wave of the pandemic in the UK.
Dr Mary Ramsay, from Public Health England, said: “This new analysis calculates how many lives they have saved in the first few months of the vaccine programme, and with every additional day more lives have and will be saved. The vaccines have an excellent safety record and I would encourage anyone who is offered a vaccine to take it as soon as possible.
“While the vaccines have a striking impact on mortality, we don’t yet know how much these vaccines will reduce the risk of you passing COVID-19 onto others. Even if you have been vaccinated, it is really important that you continue to act like you have the virus, practise good hand hygiene and stay at home.
“If future evidence shows that vaccines do help to reduce transmission, then it is likely that an even higher number of deaths will have been prevented.
“The true value of these vaccines may also be in terms of future deaths avoided, should there be resurgence of COVID-19 in the UK in the future. Older age presents the single greatest risk of death from COVID-19 – prioritisation of the COVID-19 vaccination programme has focused primarily on an aged-based strategy in order to prevent the greatest loss of life possible.”
* A second study, involving healthcare workers, has shown “strong immune response” after vaccination with the Pfizer mRNA vaccine.
Researchers from the universities of Sheffield and Oxford tested 237 workers for antibody and T-cell responses – and found “robust” responses in 99%.
Researcher Dr Thushan de Silva said: “Our results demonstrate that T cell and antibody responses induced by natural infection are boosted significantly by a single dose of vaccine. While the response to a single dose was lower in infection-naïve individuals, it was still equivalent or better than the immunity in previously infected individuals before it is boosted by vaccination.”
* A third study, published today, finds a 62% reduction in infections among care home residents after a single dose of either vaccine deployed in the UK, five weeks after vaccination.
Researchers at University College London studied outcomes for more than 10,000 residents between December and mid-March.
Researcher Dr Laura Shallcross said: “Our findings show that a single dose has a protective effect that persists from four weeks to at least seven weeks after vaccination. Vaccination reduces the total number of people who get infected, and analysis of lab samples suggests that care home residents who are infected after having the vaccine may also be less likely to transmit the virus.
“We can also infer that the vaccines protect against the highly transmissible UK variant, as this was prevalent during the study period.”
Chief medical officer Professor Chris Whitty said: “These data add to the growing evidence that vaccines are reducing Covid-19 infections and doing so in vulnerable and older populations, where it is most important that we provide as much protection from Covid as possible.”
Vaccine effectiveness of the first dose of ChAdOx1 nCoV-19 and BNT162b2 against SARS-CoV-2 infection in residents of Long Term Care Facilities (VIVALDI study). medRxiv 29 March 2021
Leave a Reply