It's all in the telling: Why Europe's approach to the AstraZeneca jab differs from ours

Paul Nuki
·5 min read
 Prime Minister Boris Johnson visits AstraZeneca in Macclesfield - Dave Thompson
Prime Minister Boris Johnson visits AstraZeneca in Macclesfield - Dave Thompson
Coronavirus Article Bar with counter ..
Coronavirus Article Bar with counter ..

We humans like nothing better than storytelling - and the more familiar the book the better. It’s why the tragedy of Romeo and Juliet has been told a thousand times. Explaining things via common narrative is one of our many tricks for making sense of the world quickly.

The oldest story of them all is the clash of nations and it’s through this prism the story of the AstraZeneca jab in Europe is oft told. How else to explain why the European Union began by limiting the vaccine's use in the old only to reverse ferret, prioritise the elderly and then restrict its use in the young?

The truth, of course, is more complicated. The bumpy ride the AstraZeneca vaccine has had in Europe (and North America) has much more to do with the different ways in which regulators approach evidence and judge risk than politics. Differing circumstances have also played an important role.

The initial decision of some countries, France and Germany included, to restrict the use of the vaccine to younger age groups stems from the fact the vaccine was not well tested among older cohorts in the original trials, where only 13 per cent of participants were age 65 and older. Add to this the fact that the tolerance and effectiveness of many vaccines falls away in older age groups and the argument for prudence becomes apparent - even though it was never clear cut.

As The Telegraph reported at the time, the European Centre For Disease Control (ECDC) was making this point long before any vaccines had been licenced. In a paper published on October 26 it said: “Before pursuing this [age-based] approach, acceptable levels of vaccine safety and efficacy need to be demonstrated among older adults. At this stage, this information is not known”.

Instead, the ECDC recommended an “adaptive” approach - one which would flex as more was learnt about the jabs.

With a glut of AstraZeneca vaccine coming our way and a second wave of the virus brewing, the UK authorities emphasised the other side of the risk-reward equation. Yes, there was a lack of evidence for the vaccine in older groups, but there was plenty of data to show Covid-19 kills older people at a much higher rate.

The risk of death from Covid for during a surge in the virus is 1-in-1,848 for a healthy 70 year old man, according to Oxford's QCovid calculator. This compares to 1-in-250,000 for a 30 healthy year old - a 135-fold difference.

With hindsight, the UK authorities made the right call. The AstraZeneca jab and others have turned out to be extremely effective in older groups and the decision to prioritise them is estimated to have saved about 10,000 lives in the UK to date. Following its “adaptive” strategy, Europe has rightly followed suit.

But what of the decision in parts of Europe and Canada to now restrict the vaccine to older groups - those above 55 or 60. How to make sense of that?

The same culture of caution - shaped by differing circumstances - may again help explain it. Europe was hit disproportionately hard by scandal following the 2009 swine flu pandemic when the Pandemrix vaccine, widely distributed to health care workers, was linked with rare cases of narcolepsy. Some 1,300 people have been affected among the roughly 30 million vaccinated across Europe, but with only around 100 in the UK.

Scientists in Germany and Scandinavia, in particular, have become black-belts in pharmacovigilance in the wake of the scandal; few if any are as good at analysing the thousands of adverse reaction reports that flow in when a new drug is launched. They are expert at sifting the early signals of a problem from the mountains of incoming chaff.

It was Norwegian and German regulators who first spotted the rare blood clotting issue now linked to the AstraZeneca jab. The UK authorities last week said they have since identified 79 cases here, putting the estimated incidence risk at about 1-in-250,000.

The reported rate “varies very much with how good the reporting system in a member state is and how good cases are being identified”, said a spokesman for the EMA last week. “In Germany, a lot of work has been done and I think there is a reporting rate of 1-in-100,000.

“We know that in the UK the reporting rate is much lower, so that can have many many causes, but for the moment I think it's safe to assume that the reporting rate is around 1-in-100,000.”

In the UK, we have now followed suit and offered a choice of vaccines to those under the age of 30. But in other countries the cut off is higher - 55 in Canada, for instance.

It is important to note that these decisions are not (for the moment at least) driven by the incidence of clots being higher in the young. There is as yet no firm data to show the risk varies with age, or indeed sex. Instead, the decision to restrict the use of the vaccine in the young comes from the other side of the equation - the much lower Covid risk in younger cohorts.

Why the difference in ages? Again that has more to do with circumstance than politics. In Europe, they currently have more of the Pfizer and Moderna vaccines and so can offer more choice. In the UK, we are more reliant on AstraZeneca - for the moment at least.

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