Data does not support this claim. Deaths of children after vaccination are too rare to inform reliable estimates. A temporary increase is possible because children with significant pre-existing health problems received vaccines before their peers.

A website claimed that the Pfizer COVID-19 vaccine “increases children’s risk of death by 5100% according to the Office for National Statistics”.

This calculation was based on ONS data (table 9), covering the period from 1 January to 31 October 2021.

In total, 107 deaths of children aged between 10 and 14 were recorded in England in that period.

Of those children, 96 were unvaccinated, seven had received a single dose and four had received two doses.

When did the vaccination of under 18s start in England?

GPs in England only began inviting clinically vulnerable 12- to 15-year-olds to receive the vaccine in August 2021. At the same time, 16- and 17-year-olds in the general population were also offered their first vaccination.

Younger children already dealing with significant health problems, and thus already at greater risk of an early death, were prioritised for vaccination and were therefore over-represented in this sample, when compared with the general population.

Mortality rates are unreliable when very few deaths are recorded, those deaths come from a very small cohort, or they cover a short period of time.

The crude calculations that led to this claim are unreliable.


The ONS provides regular information on deaths of both vaccinated and unvaccinated people in England.

Age-standardised mortality rates (ASMRs) are used to compare death rates with other countries. FactCheckNI has previously looked at ASMRs in the context of comparing excess deaths and COVID-related health inequalities.  

Information on mortality rates broken down by vaccination status is currently more readily available for adults than for children.

A temporary increase in the mortality rate for vaccinated people, which then returned to normal, was previously seen in the 18-39 age group.

The ONS bulletin that accompanied that data said that the temporary increase is probably due to the prioritisation of clinically vulnerable people for vaccination.

Clinically vulnerable people are expected to have a higher mortality rate than the general population. The mortality rate of vaccinated people returned to normal as more and more of the general population also took a vaccine.

ONS reply

FactCheckNI asked ONS about current information gaps on mortality rates of children who have been vaccinated. 

They said:“The overall ASMRs are calculated using counts of deaths and person-years in 5-year age groups. We also provide ASMRs for smaller age groups, but not for 10–18 due to the lower number of vaccinated young people and the lower numbers of deaths leading to unreliable rates.

“We are continuing to monitor and analyse data on deaths by vaccination status and will be publishing data for children in future. Health status is indeed also important to consider.

“We do not have information on whether someone was prioritised due to their health but we can use health data to determine whether someone had been hospitalised or had certain comorbidities which can help to understand how health impacts on the ASMRs, as done in our December publication, and we will be publishing an analysis of the risk factors for deaths by vaccination status including health in future.”