AstraZeneca vaccine offers 76% protection for full 12 weeks before second dose
This is very good news.
The AstraZeneca/Oxford vaccine offers 76 percent protection from Covid-19 for the full three month period between the first and second dose, a new Oxford University shows.
Sky News journalist Scott Beasley posted a breakdown of the key information in a Twitter thread.
He explained that analyses show the 76 percent efficacy of the first dose is sustained from the 22nd day after the first jab, to the full three month mark.
With the three month interval between doses being used in the UK, the second dose boosts the vaccines efficacy to 82.4 per cent.
▶️ After the second dose vaccine efficacy from two standard doses is 82.4% with the 3-month interval being used in the UK
▶️ 82.4% effective, with a 95% confidence interval of 62.7% - 91.7% at 12+ weeks
— Scott Beasley (@SkyScottBeasley) February 2, 2021
There has been much scepticism around the three month interval, but the Oxford study backs up AztraZeneca's belief that it is the most effective procedure.
Beasley tweeted that Oxford said: “Data supports the 4-12 week prime-boost dosing interval, recommended by many global regulators."
In fact, a longer gap between doses appears to increase the jab's efficacy. The study shows that a six-week interval provides a 54.9 per cent efficacy, while it rises to 82.4 per cent when each dose is 12 weeks apart.
And most crucially the vaccine does stop transmission of the coronavirus.
"Analyses of PCR positive swabs in UK population suggests vaccine may have substantial effect on transmission of the virus with 67% reduction in positive swabs among those vaccinated," he tweeted.
Professor Andrew Pollard, Chief Investigator of Oxford Vaccine Trial, co-author of the paper, said: "These new data provide an important verification of the interim data that was used by more than 25 regulators including the MHRA and EMA to grant the vaccine emergency use authorisation.
"It also supports the policy recommendation made by the Joint Committee on Vaccination & Immunisation for a 12-week prime-boost interval, as they look for the optimal approach to roll out, & reassures us that people are protected from 22 days after a single dose of the vaccine."
Read the full study here.