Vaccination is the single most effective way to reduce deaths and severe illness from COVID-19. A national immunisation campaign has been underway since early December 2020.
All vaccines and medicines have some side effects. These side effects need to be continuously balanced against the expected benefits in preventing illness.
The Medicines and Healthcare products Regulatory Agency (MHRA)'s role is to continually monitor safety during widespread use of a vaccine. They have in place a proactive strategy to do this. They also work closely with our public health partners in reviewing the effectiveness and impact of the vaccines to ensure the benefits continue to outweigh any possible side effects.
Part of their monitoring role includes reviewing reports of suspected side effects. Any member of the public or health professional can submit suspected side effects through the Yellow Card scheme. The nature of Yellow Card reporting means that reported events are not always proven side effects. Some events may have happened anyway, regardless of vaccination. This is particularly the case when millions of people are vaccinated, and especially when most vaccines are being given to the most elderly people and people who have underlying illness.
This safety update report is based on detailed analysis of data up to 24 January 2021. At this date, an estimated 5.4 million first doses of the Pfizer/BioNTech vaccine and 1.5 million doses of the Oxford University/AstraZeneca vaccine had been administered, and around 0.5 million second doses, mostly the Pfizer/BioNTech vaccine, had been administered.
As of 24 January 2021, for the UK:
- 16,756 Yellow Cards have been reported for the Pfizer/BioNTech
- 6,014 have been reported for the Oxford University/AstraZeneca vaccine
- 50 have been reported where the brand of the vaccine was not specified
- For both vaccines the overall reporting rate is around 3 Yellow Cards per 1,000 doses administered.
For both vaccines, the overwhelming majority of reports relate to injection-site reactions (sore arm for example) and generalised symptoms such as ‘flu-like’ illness, headache, chills, fatigue (tiredness), nausea (feeling sick), fever, dizziness, weakness, aching muscles, and rapid heartbeat. Generally, these happen shortly after the vaccination and are not associated with more serious or lasting illness.
These types of reactions reflect the normal immune response triggered by the body to the vaccines. They are typically seen with most types of vaccine and tend to resolve within a day or two. The nature of reported suspected side effects is broadly similar across age groups, although, as was seen in clinical trials and as is usually seen with other vaccines, they may be reported more frequently in younger adults.