Fact check: WHO says reports of serious influenza vaccination side effects are extremely rare

A post on Facebook that has been viewed thousands of times and flagged as false by users claims without evidence that the World Health Organisation is hiding information about the safety of the flu vaccine.

Reuters Fact Check. REUTERS

The post, from Jan. 8, falsely alleges that 104,000 people have died as a result of taking the influenza vaccination between 2019 and 2021 in the UK. Other claims made in the post are outside the scope of this check (here).

“A few days ago, I disclosed that heavily censored WHO data shows that the 2019-20 flu shots are known to kill 377 out of every 100,000 healthy adults,” the user wrote. He continued: “Well, after we examined UK government data from September 2019 to January 2021, we discovered that: 1. 28 million people have had the flu shot during that period. 2. 104,000 of those people have died. 3. 28,000,000 / 100,000 = 280 [x 377] = 105,560 fatal adverse events.”

This is not true. Firstly, there is no data from the WHO that says flu jabs kill. Any calculations made with reference to such data are therefore invalid.

The WHO maintains the influenza vaccination is “proven to be safe” with reports of severe side effects being “extremely rare” (here). It references Guillain-Barré Syndrome, a treatable illness affecting one in a million people that causes muscle weakness and paralysis.

Another side effect could be of a severe allergic reaction – known as anaphylaxis – to the vaccine’s ingredients, although this is also treatable and extremely rare. According to the Oxford Vaccine Group, there were a total 130 reports of anaphylaxis in the UK after all types of immunisation between 1997 and 2003. That’s a rate of 1 case of anaphylaxis in 900,000 vaccinations, considering 117 million doses were given during that six-year period (here).

Around 14 million people in the UK were vaccinated against influenza in the 2019-20 season (here). Figures for the full 2020-21 season are not yet available. The most up-to-date data shows just over 12 million flu vaccinations have been given between September and November 2020 in England alone (here, here). Figures for December 2020 and January 2021, along with figures for all months in Scotland, Wales and Northern Ireland, have not yet been released.

A total of 26 million influenza vaccinations (14 million in 2019-20; 12 million and counting in 2020-21) does not mean 26 million different people in the UK have been vaccinated. This is because people are advised to get a shot every season (here) in order to be vaccinated against different flu strains in circulation.


False. The World Health Organization maintains influenza vaccinations are safe and severe side effects are extremely rare.

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