MPs’ vaccine debate fact checked

MPs recently debated an e-petition asking the government to conduct an investigation into whether Covid-19 vaccines are responsible for an alleged “increase in heart attacks and related health issues”.  

We looked at a number of claims made about vaccines or Covid-19 during the debate on 24 October and found a number of them were misleading or missing important context. We have taken a look at a selection of them below. 

We have checked many of the claims before, including about government advice on whether pregnant women should be vaccinated, that Pfizer never tested whether its vaccine stopped transmission and whether vaccine side effects are underreported to the Yellow Card scheme.

Events reported after the vaccine are not definite ‘side effects’ caused by it

Conservative MP Sir Christopher Chope said: “The Paul Ehrlich Institute is the German regulator responsible for vaccine safety. 

“On 20 July, the Institute confirmed that one in 5,000 people was seriously affected after a vaccination. 

“That also reflected a finding that it published earlier in the year, in which the institute tried to raise the alert that one in 5,000 vaccinated people experienced a serious side effect, such as heart muscle inflammation.” 

The German Federal Ministry of Health did mistakenly tweet in July that one in 5,000 people had been affected by a serious side effect following a Covid-19 vaccine, with reference to the Paul-Ehrlich Institute, a German research and regulatory agency. 

This tweet was later deleted by the ministry and corrected with a clarification that the reports weren’t known to be caused by the vaccine, just that they had happened afterwards.

A spokesperson for the Paul Ehrlich Institute told US fact checking site Factcheck.org that “there are a couple of persisting misunderstandings that continue to lead to misinterpretations” of vaccine safety reports. 

Pfizer did say they hadn’t tested transmission

Conservative MP Danny Kruger claimed: “There was also the widespread claim that the vaccine stops transmission, so people should take the jab to protect other people. We were all told that; we all believed that for many months. Last month, we heard from Pfizer that its vaccine was never tested to see whether it would stop transmission.”

Later, Conservative MP Andrew Bridgen said: “Surely the hon. Gentleman is well aware of the much-publicised interview of a Pfizer representative by a committee of the European Parliament only a couple of weeks ago, when they admitted that they had done no testing whatever to see whether the vaccination prevented transmission of the virus.”

Mr Brigden’s comment implied that Pfizer had originally claimed its Covid-19 vaccine stopped transmission.

Pfizer was always clear that it did not test whether the vaccines reduced the risk of transmission among already infected individuals. In other words, it didn’t test whether an infected person was more or less likely to spread the disease if they were vaccinated.

But the trial did show the vaccines reduced infection risk in the first place, so reduced the risk of onward infection. The UK Health Security Agency said in January 2022: “Uninfected individuals cannot transmit; therefore, the vaccines are also effective at preventing transmission.”

Real-world studies following the roll-out of the vaccines did also indicate that vaccination reduced the risk of already-infected individuals passing on the disease. Though later studies found they were less effective at preventing transmission of the Delta and Omicron variants. 

There’s more information in our article here about the interview Mr Bridgen referred to. 

Boosters were tested on humans before UK roll-out

Sir Christopher also claimed: “The booster vaccines have not been tested on humans at all during studies; they were tested only on mice.”

This isn’t true in the UK, though it is unclear whether he was talking about the US or the UK at this point during the debate. 

This was the case in the US for the bivalent booster, which targets both the original virus and also the BA.4 and BA.5 strains of the Omicron variant (although human trial data from a slightly different booster was also considered before approval). 

But the MHRA confirmed to Full Fact that in the UK, both the original boosters and bivalent boosters on offer (which target both the original SARS-CoV-2 and the BA.1 Omicron strain) were tested on humans.

The UK Health Security Agency says the autumn booster offered will either be produced by Moderna or Pfizer. 

The “Summary of Product Characteristics” documents for the Moderna and Pfizer boosters lists that both the originals and new bivalent versions of each have been tested on humans.

Adverse events aren’t the same as confirmed ‘vaccine injuries’

Mr Bridgen claimed: “A study published in The Journal of the American Medical Association, included 7,806 children aged five or younger who were followed for an average of 91.4 days after their first Pfizer vaccination. The study showed that one in 500 children under five years of age who received a Pfizer mRNA—messenger ribonucleic acid—covid vaccine were hospitalised with a vaccine injury, and one in 200 had symptoms ongoing for weeks or months afterwards.”

It’s misleading to call these ‘vaccine injuries’. The study in question was looking at events that occurred after vaccination, but were not necessarily related to or caused by the vaccine. 

It said: “The overall frequency of adverse events after vaccination with [Pfizer’s Covid-19 vaccine] was comparable with the frequency of adverse events after vaccination with approved non–SARS-CoV-2 vaccines in children younger than 5 years.”

In the UK Covid-19 vaccines are not given to children under the age of five.

Are Covid-19 adverse events under reported?

Mr Kruger claimed that the Medicines and Healthcare products Regulatory Agency (MHRA) “suggests that vaccine injuries have been under-reported by one in 10, meaning that there may be 10 times more vaccine-related injuries than the Yellow Card scheme reports”.  

He also said: “Based on the MHRA’s research, there may be as many as 10 times more serious adverse reactions than the Yellow Card system shows.”

The Yellow Card scheme is the system in the UK which allows individuals and health professionals to report any suspected reactions to vaccines, medicines and medical devices, even if they’re not sure they were the cause.

In a response to declining rates of Yellow Card reporting in 2018, the MHRA previously said: “It is estimated that only 10% of serious reactions and between 2 and 4% of non-serious reactions are reported”. 

But it has also explicitly stated that this figure should not be used about reports about Covid-19 vaccines saying: “These estimates should not be used as indicators of the reporting rate for COVID-19 vaccines, for which there is high public awareness of the Yellow Card scheme and the reporting of suspected reactions.”

We have written about this claim before.

Effectiveness of the vaccine

Mr Kruger also claimed: “Perhaps the most egregious example [of misinformation in favour of the vaccine] was the claim that the vaccine is 95% effective…That figure refers simply to the relative risk, instead of the actual or absolute reduction in risk to an individual. The absolute risk reduction is really less than 1%.”

We have written about very similar claims in the past, when it was alleged that medical journal The Lancet had revealed this in an article. As we have explained before, relative risk reduction describes how much less your risk is if you’re vaccinated relative to someone who isn’t vaccinated, measured in percent.

So, hypothetically (these are not the actual figures), if the risk of falling seriously ill from Covid-19 for an unvaccinated person was 1% and the risk for a vaccinated person was 0.2%, the relative risk reduction would be 80% (as 0.2% is 80% less than 1%).

Absolute risk reduction, which Mr Kruger referred to, compares the difference between the proportion of people who got sick in vaccinated and unvaccinated groups. 

So in the same imagined example, the absolute risk reduction of vaccination would be 0.8 percentage points, as 0.2% (the risk for a vaccinated person) is 0.8 percentage points lower than 1% (the risk for an unvaccinated person).

Though some have argued that both measures should be published, absolute risk reduction is dependent on the underlying level of risk at the time, so any estimate of absolute risk reduction calculated as a result of the Covid-19 vaccines is dependent on the prevalence of Covid-19 at the time. 

This means that the absolute risk reduction rate inferred from trial data (which appears to be what Mr Kruger was referring to) is unlikely to have ever been relevant to the actual absolute risk reduction in the real world. 

The Lancet article we mentioned earlier compared the relative risk reductions for the vaccines in the trials (the figures given above of 90%+ and 76%) with absolute risk reductions, which it says were “1.3% for the AstraZeneca–Oxford, 1.2% for the Moderna–NIH, 1.2% for the J&J, 0.93% for the Gamaleya, and 0.84% for the Pfizer–BioNTech vaccines”. The article was first published in April 2021 (though was later corrected), so predated the detection of several variants of concern. 

These figures don’t undermine the fact that the vaccines are effective, particularly in the short term. Instead they show that people in those trials had a low baseline risk of getting ill with Covid, but the vaccines still took away most of that risk.

It should be noted that the figures above can’t be directly applied to the current risk of Covid-19 as the dominant variant has now changed. The UK Health Security Agency says: “Vaccine effectiveness against symptomatic disease with the Omicron variant is substantially lower than against the Delta variant, with rapid waning. However, protection against hospitalisation remains high.”

Some deaths have been reported from Covid-19 vaccines

Sir Christopher also claimed: “Coroners up and down the country have found in their reports that deaths have been caused directly by Covid-19 vaccines.”

It’s true that Covid-19 vaccines have been listed as the underlying cause of death for some people.

According to the Office for National Statistics, there were 47 such deaths in England and none in Wales up to September 2022. In Scotland over the same period there have been nine. There has been one registered death in Northern Ireland up to the end of March 2022, according to the Northern Ireland Statistics and Research Agency.

It is possible that the UK total may rise, if there’s been a delay in registering some deaths due to the vaccines. 

The MHRA has recorded 80 deaths from a type of blood clot that it has said may be linked with the AstraZeneca vaccine, but we can’t say how many of these were caused by the vaccine. Death certificates are the best source of data on deaths by cause.

For context, by 4 September 2022, more than 151 million doses of the Covid vaccines had been administered in the UK.

Pregnant women and vaccination

Mr Bridgen said: “The hon. Gentleman may not be aware, but contradictory evidence was issued on two separate days. One piece of advice said that pregnant and breastfeeding women could have the vaccine, and then another Government body said that that was not safe and that it did not recommend it.”

It is true that the advice on Covid-19 vaccines and pregnancy has changed over time, but this doesn’t mean they were contradictory. 

The MHRA approved the Pfizer vaccine for UK use in December 2020, but not for pregnant women. Then, in April 2021, the Joint Committee on Vaccination and Immunisation advised that pregnant women should also be offered the Covid-19 vaccine at the same time their age group was. 

This followed the publication of real-world data from the United States showing 90,000 pregnant women had been vaccinated “without any safety concerns being raised”.

What Mr Bridgen may be referring to is the fact that there was some confusion recently, when an old government document from December 2020 was widely circulated online. This document reflected the information known when it was originally published, saying “sufficient reassurance of safe use of the vaccine in pregnant women cannot be provided at the present time”,  However, the web page appeared as though it had been updated in August 2022, causing some people to suggest the government had now changed its advice for pregnant women.

But, as we’ve covered before, that document had not been recently updated. It was in a group of documents, one of which was updated on 16 August and had nothing to do with vaccines in pregnancy. This caused all documents in this group to appear as though they had been updated in August 2022, even when they hadn’t been.

The December 2020 document has now been labelled to say it “summarises the initial assessment at the time of approval in December 2020” and that “the text in the original report remains unchanged”.

Covid-19 vaccines are still recommended for pregnant women.

Myocarditis following Covid-19 infections

Conservative MP Dr Caroline Johnson claimed towards the end of the debate that “there are an estimated 1,500 cases of myocarditis per million patients with covid—far greater than the risk of myocarditis following vaccination”. 

This is the figure used by the MHRA, which says in its summary of Yellow Card reports: “Myocarditis is also known to be associated with COVID-19 infection, with an estimated 1,500 cases of myocarditis per million patients with COVID-19.”

This is correct, but is based on research carried out more than two years ago and so the findings may not reflect the rates of myocarditis related to Omicron infections. 

The MHRA told us that this statistic is based on a US study published in September 2021, which looked at the association between Covid-19 and myocarditis between March 2020 and January 2021. 

It should be noted that over this period in the US infections were overwhelmingly caused by the original SARS-CoV-2 virus, with the Alpha variant detected in the US in late December 2020. The severity of the virus is believed to have changed over time, with researchers finding that Omicron—now the dominant variant both in the US and UK—was much less likely to result in hospitalisation and death than the Delta variant. 

There has been some study of myocarditis caused by Omicron infections but it is unclear whether or not the study used by the MHRA reflects the risk of myocarditis from current Covid-19 disease caused by Omicron infections. 

Myocarditis has also been flagged as a potential risk following vaccination against Covid-19. According to the MHRA (as of 16 February 2022) the overall reporting rate across all age groups for myocarditis following vaccination with the Pfizer vaccine was 9 reports per million doses and for Moderna the overall reporting rate for myocarditis was 17 reports per million doses. 

Full Fact has contacted the MHRA, Mr Kruger, Sir Christopher, Mr Brigden and Dr Johnson for comment. 

Image courtesy of Mat Napo