The decision to postpone the UK’s second dose of Covid vaccine saved thousands of lives, further research has shown.
A study published in the British Medical Journal modeled the effect of death rate when appointments for the second stab go beyond the recommended regimen.
Scientists estimated that if the refills were spread out for more than three weeks, deaths would be reduced by up to a fifth. This was only possible with shocks that reduced death from Covid by 90 percent after one injection.
For vaccines with 80 percent initial dose effectiveness, that figure was around 11 percent, which is the case for Pfizer and AstraZeneca vaccines used in the UK.
Scientists at the Mayo Clinic, a chain of medical centers in the United States who conducted the research, said delaying dosing is likely the most effective strategy for most countries.
They didn’t say how long they modeled the space between the cans. But they said that even nations with slow roll-outs and slightly weaker bumps could benefit from any move to delay charging.
In January, the UK turned into a global outlier when it pushed back the second dose from three weeks to three months in an attempt to break the frenzied second wave. This was controversial at the time, as most studies of the vaccines had only assessed their safety and effectiveness every 21 days.
A study published in the BMJ found that the delayed strategy was always optimal when a vaccine was 80 percent or more effective in stopping serious illnesses after a dose. Vaccines that were most effective depressed the death rate the most (shown above left and right)
The UK health minister gives his fingers crossed after receiving his Covid vaccine last month. In January, the UK turned into a global outlier when it pushed back the second dose from three weeks to three months in an attempt to break the frenzied second wave
The decision to postpone dosing has allowed the UK to achieve one of the most successful vaccination programs in the world. More than 35 million Britons – more than half the total population – have already received at least one dose, and another 18 million will be fully thrust
In the most recent study, the researchers ran a simulation model that was based on real-world data from the US vaccine launch.
They examined a number of scenarios over a six month period and how they affected infections, hospital admissions, and deaths.
These included different levels of stab efficacy and administration rates, and different assumptions about the impact of the stab on transmission.
England’s Covid Vaccine Drive will open TOMORROW to children under 40
The coronavirus vaccination program in England will open for the first time tomorrow to anyone under 40.
NHS England said around one million adults, ages 38 and 39, will be invited to their push starting Thursday morning.
You will be offered either the Pfizer or Moderna vaccine last week based on directions from medical regulators.
The Joint Committee on Vaccination and Immunization said those under 40 should be given an alternative to the AstraZeneca sting because of their association with rare blood clots.
According to the NHS Digital Bulletin, 38- and 39-year-olds who have already booked a first dose of the UK vaccine will have their appointments canceled.
Individuals who qualify for a stab will be invited through a text from ‘NHSvaccine’ which contains a web link to the health service’s online booking service.
Those who can’t access the internet can instead call 119 to schedule an appointment at one of the 1,600 locations where the vaccines are given across England.
To date, more than a quarter of the entire UK population – 18.1 million – have been fully vaccinated against Covid and more than half – 35 million – have received the first dose.
The NHS National Medical Director Professor Stephen Powis said the success of the rollout was due to “careful planning and precision by NHS staff”.
It found that the delayed strategy was always optimal when a vaccine was 80 percent or more effective in stopping serious illness after a dose.
The policy could prevent between 47 and 26 deaths per 100,000 people, depending on how quickly countries deliver the shocks, the researchers said.
For shocks 90 percent or more effective after a dose, countries could reduce the death rate by 226 per 100,000 to 179 (20 percent) if they delayed the second injection.
Vaccines that are 80 percent effective after the first time could reduce the death rate from 233 to 207 (11 percent).
For shocks with an initial dose of 70 percent effectiveness, there was no measurable difference in lives lost.
The study’s lead author, Professor Thomas Kingsley, a medical expert at Medicine Mayo Clinic, said, “The reluctance to delay a second dose is understandable given the limitations of a non-randomized trial design.
‘However, our agent-based model can provide estimates of the relative differences between these strategies that can be useful in making policy decisions.
“Importantly, our results suggest that this is also the optimal strategy for preventing deaths under certain conditions.”
British experts commented on the study, saying the UK’s decision to postpone the delay has been confirmed.
Dr. Peter English, former chairman of the British Medical Association’s Public Health Medicine Committee, said, “It became clear that while the bottleneck was vaccine availability, providing far more lives could be saved and hospital and intensive care units avoided by providing one dose for as many people as possible, especially those at highest risk of serious Covid disease, before a second dose is given.
‘This was the basis for the UK’s decision to postpone the second dose to 12 weeks, which has been shown to be extremely effective.
‘This study uses models to show that this is likely to apply not just domestically, but globally. Delaying the second dose worldwide will be the quickest to control the disease.
Concerns have been raised about the lack of evidence of effectiveness when delaying the second dose increases the prime boost interval.
‘These concerns are misplaced. Everything we already knew about vaccines also tells us that a longer prime-boost interval increases the breadth and depth of the immune response and provides longer lasting immunity that is likely to offer better cross-protection against variant strains.
‘There is relatively little knowledge about this specifically related to Covid vaccines – although such data, as we have seen, agrees with it.
‘It goes beyond this paper; However, it is likely that lengthening the Prime Boost interval will result in better, longer-lasting immunity and protect more people, faster. ‘
The decision to postpone dosing has allowed the UK to achieve one of the most successful vaccination programs in the world.
It was made in the face of an outbreak of the highly communicable Kent variant that plunged the country into a third national lockdown, causing even more deaths and hospitalizations than the first wave.
More than 35 million Britons – more than half the total population – have already received at least one dose, and another 18 million will be fully thrust.
A comprehensive analysis by Public Health England earlier this week found that a single dose of the Pfizer or AstraZeneca vaccine reduced the number of deaths by 80 percent.
The UK vaccine rollout review also found the Pfizer vaccine reduced deaths after two doses by 97 percent. Such data are not yet available for AstraZeneca.