In under 24 hours of announcing that AstraZeneca's Vaxzevria vaccine would not be given to adults under 30 the UK government has moved to restore confidence in its medical regulator. Health minister Matt Hancock insists the public should take confidence from the decision claiming it is proof the monitoring system is transparent and robust.

"People can be reassured that we have the high class safety system run by our world class regulator and then we're totally transparent with all of the side effects, no matter how extremely rare they are like these ones,”he told Sky News.

Adults under the age of 30 living in the UK will be offered an alternative vaccine to the Vaxzevria jab because of growing evidence it could cause blood clots.

Figures up until the end of March have found that 79 people (51 women and 28 male) who received the vaccine suffered blood clots, resulting in 19 deaths. The ages of those who died ranged from 18 to 79, including three people under 30.

Twenty million people have so far received the jab - based on those numbers there is a one in four million chance of developing a blood clot.

But the UK's Medicines and Healthcare Regulatory Agency (MHRA) and the Joint Committee on Vaccination and Immunisation (JVCI) has now tweaked the UK's vaccine rollout program.

READ MORE:

France wants U.S. to return 1904 Olympic medals

Who should be vaccinated first?

Can horses help ease depression?

The two bodies have advised that young adults under the age of 30, with no underlying health conditions, should be offered an alternative vaccine to AstraZeneca when available.

Pregnant women have been advised  to discuss with their doctor whether they'd benefit from having the AstraZeneca vaccine. 

Anyone with a history of blood disorders and an increased risk of blood clots should only have the AstraZeneca jab where benefits outweigh potential risks. 

Meanwhile, those people who have experienced clots after their first dose have been told they should not get a second jab of the AstraZeneca vaccine.

A trial in Britain how the AZ vaccine might impact 6-17 year olds has also been paused, while an investigation takes place.

UK Prime Minister Boris Johnson says people should listen to medical regulators and keep getting their jabs, safe in the knowledge that blood clots are a very rare occurrence.

He said, "We will follow today's updated advice, which should allow people of all ages to continue to have full confidence in vaccines, helping us save lives and cautiously return towards normality."

The AstraZeneca vaccine is made from a weakened version of a common cold virus from chimpanzees - which has been modified to look more like coronavirus - although it can't cause the illness. 

Once injected, it teaches the body's immune system how to fight the real virus, should it need to. Unlike the Pfizer vaccine it can be stored in a normal fridge and not at minus 70 degrees Celsius. Which makes it far easier to distribute.

Video editor: Steve Egar