Two German newspapers reported last night that German government sources had told them the Oxford-AstraZeneca vaccine is only 8 per cent effective (or less than ten per cent) in the over-65s.

But there are good reasons to think these reports are incorrect.

The main data we have on the jab was published in the Lancet medical journal back in November. Scientists were last night struggling to reconcile this with the figures relayed by the Handelsblatt and Bild newspapers.

Adam Finn, professor of paediatrics at the University of Bristol, said that having read the Lancet research, he had “no idea where the 8 per cent figure comes from”.

AstraZeneca themselves said the claims were “completely incorrect” and that the Lancet paper “demonstrat[ed] that older adults showed strong immune responses to the vaccine, with 100 per cent of older adults generating spike-specific antibodies after the second dose”.

The University of Oxford said “there is no basis” for the figures relayed by the two newspapers.

“The results of the clinical trials have already been published transparently in five peer-reviewed scientific publications showing similar immune responses in younger and older adults” they said, adding: “preliminary efficacy data in older adults supports the importance of this vaccine for use in this population”.

Now the German government, which was apparently the source of the newspapers’ story, has said it cannot confirm the reports. It suggests there’s been a mix-up between the proportion of study participants aged 56 to 69 – who comprise about 8 per cent of the sample – and the efficacy of the vaccine in those groups.

We can do the maths on this ourselves. Across the three studies and all the “dosing strategies” in the Lancet paper, there were 11,636 participants in total, of which 974 were aged 56 to 69. That works out at 8.4 per cent.

Though we still don’t know if that’s what led the two newspapers to publish their claims.

It’s worth saying that there are some limitations on what the Lancet paper can tell us about older adults.

As Professor Finn pointed out last night: “Elderly people were recruited to the UK phase 3 relatively late and were relatively well shielded, so there were few cases of COVID that had occurred at the time of submission of data to [the UK regulator, the] MHRA for approval.”

He said it was possible that there may have been more information on this age group at the time the jab was put in front of the European regulator, the EMA. (Though his comments came before the German government’s statement this morning).

The German government says the EMA is still evaluating the studies and will release its conclusions on Friday.

FactCheck verdict

Two German newspapers reported last night that they had been told by German government sources that the Oxford-AstraZeneca is only 8 per cent (or less than ten per cent) effective in adults over 65.

There are good reasons to think these reports are incorrect. As well as the manufacturers denying the claims, other experts were unable to reconcile the figures with the best data we have so far – a paper published in the Lancet.

Now the German government itself has said it cannot confirm the newspaper reports, and suggests someone has confused the proportion of study participants aged 56 to 69 (who made up 8 per cent of the sample) with the efficacy of the vaccine in older adults. Though we do not yet have a clear account of how the newspapers came up with their figures.

It is true that we are still waiting for more information on the precise efficacy of the jab in elderly populations, but we should have a better sense of this on Friday when the European regulator releases its assessment.

Until then, we should consider what Stephen Evans, Professor of Pharmacoepidemiology at the London School of Hygiene and Tropical Medicine told FactCheck today: “Leaks on scientific issues are very dangerous indeed.”