In trials, the vaccine proved highly efficient at stopping people developing symptoms Off Cove in 19, the results suggest 70% protection, but by adjusting the dose, the protection could rise to as high as 90% on while other vaccines have reported higher protection.

The great advantage of the Oxford one is that it's cheaper.

It's far easier to store on, thus easier to deliver around the world now, during the day, the prime minister described the results is incredibly exciting, but urged caution in the meantime as he outlined the restrictions for England after the current lock down ends on the second of December.

We'll have more on that in just a moment.

First, our medical editor, Fergus Walsh, reports on the Oxford vaccine.

For the first time since this wretched virus took hold, we can see a route out of the pandemic.

We are just delighted here in Oxford.

Huge, huge, Congratulations.

See you all on your teams.

It's the third goal in the back of the net.

Now Oxford has created a vaccine not just for Britain but for the world, the scientists involved say.

It brings us closer to a return to normal life.

I can definitely see a future beyond the pandemic.

I think that we will be able to roll out vaccines in the first half of next year and have a big impact here in the UK But for humanity we have to be able to distribute all around the world, and that's going to take a bit longer.

In less than a year, scientists here have created a brand new vaccine and run large scale trials.

Now, at last, they know it works.

There were more than 20,000 volunteers on the trial in the UK and Brazil.

Overall, two doses of the vaccine were around 70% effective in preventing Cove in 19.

But among volunteers who got a half dose followed by a full one, effectiveness rose to 90%.

Importantly, there were no cases of serious co vid disease among those who got the vaccine.

Thanks, So I got over here.

Three UK has preordered enough doses to immunize 50 million people in the UK Theo elderly in care homes would be first in line, then the over eighties and frontline health workers, along with Pfizer and Madonna.

It means there are now three co vid vaccines, which could be approved next month.

Like the Pfizer and Madonna vaccines, the key to the Oxford Jab is that spike protein, which sits on the surface of coronavirus scientists have taken the gene for this protein on put it into a virus that causes the common cold in chimpanzees.

The virus has been modified and disabled so it can't cause disease in humans.

Once in the body, the vaccine instructs cells to make the coronavirus spike protein.

This prompts the immune system to create Y-shaped antibodies. In the event of future exposure,

these should latch onto coronavirus on prevent infection on it stimulates T cells, another part of the immune system.

These should destroy cells that have become infected.

This is a really important day for scientists here in Oxford on for the fight against coronavirus.

Data is still being analyzed, but their vaccine appears to prevent serious illness with co vid on most infections.

Now that could have a major impact on the pandemic here in the UK on worldwide.

Although the vaccine was created in record time, Oxford says no shortcuts have Bean taken with safety on side effects have been mostly mild.

Edward was one of the very first volunteers.

It's pretty amazing how fast everything is, but really, how careful and considered everything is being done.

Everything is that we can trust it.

And so it's really exciting to see the results.

AstraZeneca Oxfords, commercial partner has pledged never to make a profit from the vaccine in poorer countries on their jab is far cheaper, easier to store and transport around the world than others.

The supply chain that we put in place for next year will give us a capacity of up to three billion doses, which will include not just the developed world but many regions of developing world as well.

Because this vaccine is just refrigerated, it makes it much easier to distribute and administer.

But don't underestimate the hurdles ahead.

Immunizing the UK, let alone the world, will be a huge undertaking.

Drive through centers like this one in Greater Manchester currently providing flu jabs, are likely to be used for covert vaccines.

And even if a million adults a week are immunized, it'll be months before these vials helped clear a path through the pandemic on Fergus is back from Oxford on with me down the studio.

This is the third vaccine we've been discussing.

Lots of excitement.

Understanding of this one Fergus question for lots of people at home is when you know when will we see the vaccine?

When will people actually be treated with it?

This astonishing here that we now have three vaccines that can prevent serious covert infection.

It's going to take a week or two for AstraZeneca to get their paperwork together on submitted to regulators.

Fights has already done that.

We might see the first vaccines being approved early in December, and we might see some immunization before the end of the year.

But the vast majority is going to be done in 2021.

The prime minister says he'd like the vast majority of vulnerable people to be in immunized by Easter in early April.

Well, there are 12 million over 65 toe.

Add to that all the frontline healthcare workers.

So the younger you are, the longer you're gonna have to wait.

If you're under 50 you might have to wait till the summer.

But we do need people.

We do need adults to take up the offer of vaccination.

It's not gonna be compulsory.

We need maybe 60 or 70% of adults to be immunized to curb the spread of the virus.

Now, we don't know how long protection will last.

At some point, we may need booster doses.

So we shouldn't expect the vaccine to change our lives this winter.

But thanks to science, the path out of this pandemic is looking ever clear.

Fergus.

Good to talk to you again.

Thank you very much.

Fergus Walsh.

There are medical editor.