British Prime Minister Boris Johnson poses for a photo with a vial of the vaccine candidate Covid-19 from the University of AstraZeneca / Oxford.

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The UK government and health experts in the country have rushed to defend the coronavirus vaccine developed by AstraZeneca and Oxford University the following concerns about a possible association with blood clots.

On Wednesday, UK health and vaccine regulators issued an amendment to guidelines on who should receive the shot. They now recommend that people under the age of 30 get an alternative vaccine if they fear it could, on rare occasions, lead to a serious blood clot.

Following a safety review of the AstraZeneca vaccine triggered by concerns about reports of rare bleeding disorders in a small number of people vaccinated, both the UK and European Medicines Agency (MHRA and EMA, respectively) emphasized that the benefits of the sting outweighed them Risks.

Amid fears that the vaccine’s reputation could be further harmed, experts rushed to defend it – and a Twitter user said the officials have apparently gone into “damage control” mode.

On Thursday, the British Minister of Health emphasized that the risk of a blood clot after receiving the AstraZeneca Covid vaccination is roughly the same as that of a long-haul flight. He said the safety measures surrounding the vaccine are robust and allow regulators to “detect this extremely rare occurrence”.

On the chances of developing a blood clot, Matt Hancock said BBC Breakfast:: “The security system that we have around this vaccine is so delicate that it can capture events from four to a million. I was told it was the same risk of taking a long-haul flight.”

Meanwhile, UK Prime Minister Boris Johnson, who himself received a first shot of the vaccine, said, “The best thing people should do is see what the MHRA, our independent regulator, says – that’s why we have it, that’s why Is it you.” independently.

“Her advice to people is to keep going out, get your push, get your second push,” he added on Thursday.

Amid growing concerns that Wednesday’s announcement could result in a vaccine delay in the UK, where the vaccination program has so far been well advanced and over 31.7 million adults have received a first dose of vaccine to date. The UK has been working through priority groups for a vaccine, with those under 50 (with no underlying health conditions) standing up for a shot next.

UK Deputy Chief Medical Officer Jonathan Van-Tam also tried Wednesday to downplay the concerns, saying the reports of blood clots were “vanishingly rare”. He also noted that “changes in preference for vaccines are business as usual and this is a correction of course.”

“When you are sailing across the Atlantic in a massive liner, it really doesn’t make sense that you don’t have to make at least one course correction during this voyage,” he said at a news conference, adding that the vaccines were being kept under “very careful scrutiny . “

Vaccine hesitation “clearly a problem”

Andrew Freedman, an infectious disease reader at Cardiff University School of Medicine, was among the experts who said the UK’s move to restrict use of the AstraZeneca vaccine made sense.

“It sounds like a sensible decision based on the evidence we have so far of a likely causal link between the AZ vaccine and these very rare thrombotic side effects that have been identified,” he told CNBC on Thursday. However, he noted that the vaccine hesitation was now “clearly a problem”.

“It will be important to continue to emphasize the message that vaccinations save lives and have saved thousands of lives in the UK,” he added.

Andrew Pollard, Professor of Pediatric Infections and Immunity at Oxford University who co-developed the shot with AstraZeneca, said in a statement Wednesday that “Safety was our priority in developing the vaccine … and we are reassured about it see that safety surveillance will continue under the close scrutiny of regulatory and health authorities when the vaccine is rolled out globally. “

I’m not sure

Countries in mainland Europe will likely have a harder time convincing their citizens that the AstraZeneca vaccine is safe to this day, given the numerous doubts and disputes about the shot and deliveries.

After a second review of the shot, the European Medicines Agency also decided the vaccine was safe on Wednesday but said it had found a “possible link” between the bite and very rare cases of blood clots. However, the EMA has not placed any age restrictions on recipients.

The agency’s executive director Emer Cooke wanted to reassure the public, noting that the researchers were still trying to find out what caused a small number of rare but serious blood clots, including cerebral venous sinus thrombosis (CVST).

The issue “clearly illustrates one of the challenges of large-scale vaccination campaigns when millions of people receive these vaccines. Very rare events can occur that have not been identified during clinical trials,” she said.

EU leaders met on Wednesday evening but failed to agree on a coordinated strategy for the AstraZeneca vaccine.

So far, four European countries including Denmark and the Netherlands have stopped using the AstraZeneca vaccine altogether, while a number of other countries including Germany, France and Spain have set age restrictions on the shot.

Most of the cases of blood clots identified by regulators occurred in women under 60 within two weeks of the shot. However, officials are still investigating specific risk factors that could have contributed to this phenomenon.

Unusual clotting with low platelets is added to the product information of the vaccine as a “very rare” side effect, the EMA added.