Three people under the age of 30 have died as a result of blood clot complications after receiving the AstraZeneca vaccine, the Medicines and Healthcare products Regulatory Agency (MRHA) has said.

Dr June Raine, chief executive of the MHRA has said that more than 20 million doses of the jab have been administered in the UK and stressed no effective medicine or vaccine is without risk.

Up to March 31, the MHRA has received 79 reports of blood clots accompanied by low blood platelet count, all in people who had their first dose of the vaccine, out of millions of doses given.

Of these 79, a total of 19 people have died, although it has not been established what the cause was in every case.

The 79 cases occurred in 51 women and 28 men, aged from 18 to 79.

Of the 19 who died, three were under the age of 30, the MHRA said.

Some 14 cases of the 19 were cerebral venous sinus thrombosis (CVST), a specific type of clot that prevents blood from draining from the brain.

The other five cases were other kinds of thrombosis in major veins.

The MHRA has concluded that the balance of risk for the vaccine is very favourable for older people but more finely balanced for younger groups.

The committee concluded that the benefits of the jab outweigh the risks, but as people under 30 are at less risk of coronavirus they should be offered an alternative jab.

Guidance from the government’s vaccine advisory group, JCVI has said that people under 30 under who have already received the jab should go ahead and receive their second dose.

Only people who suffered from blood clots after their first dose should avoid a second vaccine, the MHRA said.

The MHRA said the benefits of the Oxford/AstraZeneca vaccine continue to outweigh any risks for most people, as European regulators ruled that unusual blood clots were “very rare side effects” of the jab.

Findings found there were still huge benefits of the vaccine in preventing Covid-19, and has not concluded that the vaccine causes rare clots, although it says the link is getting firmer.

Dr June Raine, told a briefing the clots were “extremely rare” and the benefits of the jab were clear.

She added: “The evidence is firming up and our review has concluded that while it’s a strong possibility, more work is needed to establish beyond all doubt that the vaccine has caused these side effects.

Prime Minister Boris Johnson said the Government believes the Oxford/AstraZeneca vaccine is “safe”, telling reporters on a visit to Cornwall: “But the crucial thing for everybody is to listen to what the scientists, the medical experts have to say later on today.”

He added on the vaccination programme: “You can really start to see some of the benefits of that – it’s pretty clear that the decline in the number of deaths, the decline in the number of hospitalisations is being fuelled, is being assisted, the steepness of that decline is being helped by the rollout of the vaccines so it’s very important for everybody to continue to get your second jab when you’re asked to come forward for your turn.”