Sage scientist 'not worried one bit' by AstraZeneca safety concerns over rare blood clot

Andy Wells
·Freelance Writer
·4 min read
In this photo illustration, the NHS staff member holding the Oxford AstraZeneca Covid-19 vaccine vial with a syringe. (Photo by Dinendra Haria / SOPA Images/Sipa USA)
An NHS staff member holding the Oxford AstraZeneca COVID vaccine vial with a syringe. (PA)

A scientist who advises the government on the coronavirus pandemic has said he is “not worried one little bit” by safety concerns about the Oxford/AstraZeneca vaccine.

Professor Calum Semple, who sits on the government’s Scientific Advisory Group for Emergencies (Sage), insisted the vaccine was “safe” after reports it has been connected to a rare form of blood clot among some adults who have taken it.

A trial of the vaccine in children has been paused while regulators investigate the reports, but Semple said the decision to pause had been made out of “exceptional caution”, and urged people to continue accepting the jabs.

Speaking in a personal capacity, Semple told LBC radio: “I’ll take myself, I’m 53, my risk of death from COVID is about one in 13,000, for me it’s a no-brainer, I need to have the vaccine.”

Britain's Prime Minister Boris Johnson receives his first dose of the AstraZeneca/Oxford Covid-19 vaccine, administered by nurse and Clinical Pod Lead, Lily Harrington, at the vaccination centre in St Thomas' Hospital in London on March 19, 2021. - British Prime Minister Boris Johnson said on Wednesday he will take the vaccine developed by AstraZeneca after a number of European countries halted their rollout of the jab over safety fears. (Photo by Frank Augstein / POOL / AFP) (Photo by FRANK AUGSTEIN/POOL/AFP via Getty Images)
Boris Johnson receives his first dose of the Oxford/AstraZeneca COVID vaccine at the vaccination centre in St Thomas' Hospital, London. (Getty)

He later added: “This vaccine is safe. What do I mean by safe? You can look right, look left, look right again, cross a road, it’s safe to cross because you don’t see any cars [but] you can trip, you can stumble.

“Nothing is risk-free, but is the vaccine safe? I would say yes.”


Assessments are underway into the very rare and specific type of blood clot in the brain, known as cerebral venous sinus thrombosis (CVST), occurring together with low levels of platelets (thrombocytopenia) following vaccination in adults.

The World Health Organization (WHO) and the European Medicines Agency (EMA) are expected to announce findings of their assessments this week.

Watch: PM urges people to continue getting AstraZeneca vaccine

The UK’s regulator, the Medicines and Healthcare products Regulatory Agency (MHRA), is also investigating reports but has not confirmed when it will present its findings.

Both the MHRA – which said it had identified 30 cases of rare blood-clot events out of 18.1 million doses of the jab administered up to and including 24 March – and the WHO have said that to date the benefits of the vaccine in preventing coronavirus outweigh any risks.


Others have also rallied around the AstraZeneca vaccine in the face of the investigations into its safety.

Ravi Gupta, professor of clinical microbiology at the Cambridge Institute for Therapeutic Immunology and Infectious Diseases, told Sky News the vaccination programme should continue until more is known on blood clots and the AstraZeneca vaccine.

He said people in their “20s, 30s, 40s and 50s” are at risk of severe COVID “and there is an argument for vaccination to continue in those individuals because the rate of this blood clot disorder is extremely low, although slightly elevated against background levels”.

 A general view of a NHS Covid-19 mass vaccination centre that has been set up at Life Science Centre.
Serval mass vaccination centres now opened to the general public as the government continues to ramp up the vaccination programme against Covid-19. (Photo by Nicolas Briquet / SOPA Images/Sipa USA)
An NHS COVID-vaccination centre at the Life Science Centre in Newcastle upon Tyne. (Getty)

Asked if he would take the jab, he said: “I think that’s on balance at the moment – there’s still transmission of COVID, and there is a risk to all of us of being infected, particularly as the economy is being opened up and society’s opening up, we are at risk of getting severe infection.

“So I would certainly be going forward for that vaccine in the current situation.”

Professor Sir Kent Woods, former chief executive of MHRA, said he has “no reservations” about the vaccine, telling LBC: “The risks of COVID are much higher.”

Conservative former health secretary Jeremy Hunt said there is “urgency” over the MHRA concluding its investigations, adding that “no medicine is 100% safe”.

People queue to enter the NHS Covid-19 vaccination centre in Westfield Stratford City shopping centre in east London on February 15, 2021 as Britain's largest ever vaccination programme continues. - Prime Minister Boris Johnson called Britain hitting a target of inoculating 15 million of the most vulnerable people with a first coronavirus jab
People queue to enter the NHS COVID-vaccination centre in Westfield Stratford City shopping centre in east London. (Getty)

Adam Finn, a professor of paediatrics at the University of Bristol who also sits on the Joint Committee on Vaccination and Immunisation, said concerns over the jab are being “very thoroughly” investigated – and it “could potentially” affect the rollout of the vaccine.

Figures released on Tuesday showed a total of 5,496,716 people in the UK have now received both doses of a COVID vaccine and are fully vaccinated against the virus – the equivalent of 10.4% of the adult population.

Some 31,622,367 people (60% of adults) have received a first dose.

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