In the end, the AstraZeneca vaccine just wasn’t as good as its rivals

The AstraZeneca jab was a shot in the arm for Britain: a timely home-grown triumph that helped the country limp back to normality after nearly a year of stringent Covid restrictions.

But within months, the Oxford vaccine had become inocula non grata and is now no longer used in the UK, having been shelved in favour of Pfizer and Moderna. 

In some ways its descent from hero to zero was deeply unfair.

The first rumours that the vaccine was unsafe were undoubtedly sparked by political sour grapes – a smokescreen drummed up by disgruntled EU leaders, desperate to justify why their own citizens did not have the same early access to jabs as Britons.

France stoked mass confusion by first banning the AstraZeneca vaccine in the over-65s, then suspending it completely, before finally ordering that it not be given to under-55s amid concern over blood clots. 

It was a case of throwing mud until some stuck and, through good luck rather than good judgment, the clotting issue turned out to have some adherent veracity. 

By April 2021, there had been 79 reports of blood clots and 19 deaths in Britain, leading the Medicines and Healthcare products Regulatory Agency (MHRA) to rule it was no longer worth the risk for young people. 

Crunching the numbers showed that at the time, for the under-30s the vaccine would prevent just 0.8 people per 100,000 being admitted to hospital with Covid, yet could cause harm to 1.1 in 100,000. 

Many questioned why the issue had not been picked up in trials. But although vaccine trials consist of tens of thousands of people they are still too small to pick up rare, population-level events. 

“You can’t pick these kinds of things up until you have literally deployed tens of millions of doses of vaccine,” Prof Sir Jonathan Van-Tam said at a Downing Street press conference in April 2021, in which the Government announced a “course correction”.

He was right, of course. The risk of clots from the jab is very low, around seven in a million – far lower than from the contraceptive pill – so trying to tease out a real effect from the usual background rate took months and millions of injections. 

But the clotting issue was handled badly, stoking distrust and making it difficult to report on without being labelled a troublemaking anti-vaxxer.

In March 2021, The Telegraph was one of the first newspapers to imply a causal link between the jab and blood clots after Norwegian scientists suggested a possible mechanism. 

On the day we published the story we received a threatening phone call from a senior official at the MHRA warning that The Telegraph would be banned from future briefings and press notices if we did not soften the news. 

Another well-known Cambridge academic got in touch to complain about our “disgraceful fear-mongering headline” on the story, claiming that it would discourage vaccine uptake and cost lives. 

We politely pointed out that hiding the facts from people was not helpful and could also cost lives. The academic did not respond. 

In February this year, TikTok removed an audio clip in which I discussed whether the benefit of vaccination was worth the risks for young people, claiming it had breached community guidelines. 

After we showed that the Government’s own website acknowledges the link, the clip was reinstated. 

All of this shows a troubling paternalism in government, academia and some media outlets who believe that the public is not capable of weighing up the pros and cons of medical interventions and so must be shielded from the truth.

Handled better, the AstraZeneca jab may have rebounded from its side-effect troubles, but by the autumn of 2021 new problems were becoming apparent: it was simply not as effective as the mRNA vaccines. 

Figures showed that AstraZeneca’s effectiveness against symptomatic disease fell to 47.3 per cent from 62.7 per cent after 20 weeks, compared to 69.7 per cent from 92.4 per cent for Pfizer. Moderna was slightly higher.

And while early studies suggested that the AstraZeneca jab might reduce transmission by up to 67 per cent, by October 2021, Oxford University found it was less effective than Pfizer, with the transmission impact disappearing entirely after 12 weeks. 

By the following June, the World Health Organisation issued interim recommendations warning the AstraZeneca vaccine had “no substantive evidence of impact on vaccine transmission”. 

So with diminished performance and an increasing tally of blood clots, it is easy to see why the Government chose to move away from a vaccine that it had once championed.

That is not to say the AstraZeneca jab does not have a positive legacy. At a population level, it undoubtedly saved lives. Oxford University estimates that 6.3 million lives were saved in the first year of the rollout alone.

And it is easy to forget the desperate clamour for a jab that could get the country moving again in 2020. 

We now know the catastrophic harms of lockdown, and if we had spent many more months developing a more effective and safer vaccine, the longer-term impact of bringing the country to a standstill would have proved far more deadly than any of the rare side effects we have seen. 

But there remains the awkward truth that those at the lowest risk from Covid – the young and the healthy – were the ones who suffered the most from the jab. 

Most recent figures show that the NHS Vaccine Damage Payment Scheme has received 6,885 claims to date, of which 148 individuals or families have already been notified they are entitled to compensation. More than 95 per cent of those payouts relate to AstraZeneca.

Oxford University still has faith in its vaccine platform, announcing last month it will use the same ChAdOx1 delivery system to develop a jab for the Middle Eastern Respiratory Virus (Mers). 

The platform uses a harmless adenovirus to shuttle genetic material from the virus into cells, and research by AstraZeneca and Cardiff University has shown it is probably this method that can trigger a dangerous clotting response in a small number of people.

Potentially, armed with this information, vaccines can be improved or those at risk identified before the jab, although Oxford said it will not be making alterations.  

Regardless, unlike Covid, the death toll of Mers is so high that any risk from the vaccine is likely to be far outweighed by the benefit.