The first people taking part in the national roll-out of a coronavirus vaccine were given their jabs today.
British regulators are the first in the world to approve the mass use of the Pfizer/BioNTech Covid-19 vaccine, and more are in the pipeline.
The makers of the Oxford/AstraZeneca vaccine became the first manufacturers to publish the results of clinical trials in a peer-reviewed journal today. They say they hope to get regulatory approval within weeks.
FactCheck is answering as many reader’s vaccine questions as we can.
But there are some questions that no one knows the answers to yet. Here’s what we still don’t know.
How much vaccine will we get before Christmas?
The first batch of Pfizer vaccine to arrive in the UK consists of just 800,000 doses, but NHS bosses say they expect to have more by the end of the year.
Saffron Cordery, deputy CEO of NHS Providers, said this weekend: “We are expecting in the low millions, so up to four million doses, to be with us by the end of December.”
The health secretary, Matt Hancock, said today that he did not know the precise number.
If the AstraZeneca vaccine is approved this month, there are already several million doses in the country waiting to be used too, according to the UK Vaccines Taskforce. But we don’t have exact numbers.
Most of AstraZeneca’s product is expected to be manufactured in the UK if regulators give the company the green light.
The British government has placed orders with five other manufacturers who have vaccines in the pipeline.
Will everyone get the same jab?
With uncertainty over the supply of all the leading vaccines, it’s possible that different people will get different vaccines at different times – or even that the same person gets two different vaccines.
The Vaccines Taskforce says the UK is considering launching trials to see whether there is a benefit from “mixing and matching” different vaccines – giving someone a shot of one vaccine then a second booster jab with a different one.
This approach, sometimes called “heterologous prime-boost”, has been around for decades and has been found to lead to improved immune response in some clinical trials.
If successful, it could lead to better results than treating people with the same vaccine. But we will have to wait until more than one vaccine is licensed for use in the UK before British trials can begin.
Which vaccine is the best?
That means that of all the people in clinical trials who caught Covid-19, more than nine out of ten were in the placebo group, not the group treated with vaccines.
The Oxford/AstraZeneca vaccine has demonstrated lower overall efficacy in trials, although the data suggests a protocol of giving people a half-dose followed by a full one could improve its effectiveness.
The overall efficacy of 70.4%, based on 11,636 trial participants across Britain and Brazil, is still significantly above the minimum expectations set out by regulators, and this vaccine is considerably cheaper and easier to store than others.
There is still uncertainty about whether any of the leading vaccines are able to stop people with no or mild symptoms from passing on the virus to others.
And there is no way of knowing yet how long immunized people will be protected from the virus.
When will social distancing measures end?
This is perhaps the most important question for many of us, but the government is refusing to set out a date for the likely lifting of the restrictions designed to slow the spread of the virus.
This morning the health secretary, Matt Hancock, said in broadcast interviews today that he hoped to lift restrictions in spring next year, but he urged people to follow existing guidelines in the meantime.
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