Press release

Major university study sheds light on vaccine side effects

Published on 21 July 2021

Less than one in 12 Covid-19 vaccine recipients reported significant side effects in the week following their jab, a major University of Dundee study has found.

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Less than one in 12 Covid-19 vaccine recipients reported significant side effects in the week following their jab, a major University of Dundee study has found.

Additionally, researchers from the University’s School of Medicine found that almost half of those surveyed said they felt better after receiving their vaccination.

The VAC4COVID study has recruited more than 12,000 people from across the UK, with participants reporting changes in their health and wellbeing after receiving their vaccine.

The study has also helped to identify the most commonly reported side effects following a vaccine, including fever, headaches and fatigue.

Dr Amy Rogers, a VAC4COVID study doctor, explained that “Vaccines work by stimulating our immune systems to mount a defence against infections. These are just the sort of symptoms that we would expect at least some people to report after receiving an effective vaccine.

“The side effects of Covid-19 vaccination have been a talking point, but the figure of 7.9% is very much in line with what we expect from any vaccination, such as seasonal flu. That should make these results very reassuring for anybody still concerned about the possibility of side effects from their Covid-19 vaccination.”

Figures from the study show that 7.9% of participants reported a change in their health which they considered sufficient to disrupt their usual daily activities in the seven days after receiving their inoculation. In contrast, 45% of VAC4COVID participants reported feeling better after receiving a jab.

While most people do not experience any significant side effects as a result of vaccination, the study has identified that the different vaccines used in the UK do possess slightly different side effect profiles.

Recipients of the Oxford-AstraZeneca vaccine were more likely to report headaches and fatigue after their first dose than their second. Meanwhile, those who received the Pfizer-BioNTech vaccine tend to report more side effects after their second dose. As more vaccines become available, such differences may help inform health authorities as to which vaccines to use.

Professor Tom MacDonald, the VAC4COVID Chief Investigator, said, “This study is completely independent, with no involvement by vaccine manufacturers. We believe this is important and means the public can have confidence in our findings.”

The research team are continuing with the study and are especially keen to hear from more people aged 18-30 and pregnant women, to help learn as much as possible about how people feel after these vaccines.

“By taking part in this important research, anyone who has one or two vaccines, or has not yet been vaccinated against Covid-19, can help us learn more about how people feel after vaccination,” Dr Rogers added.

Anyone in the UK aged 18 or over who has an email address can take part in the VAC4COVID study via


Grant Hill

Senior Public Affairs Officer

+44 (0)1382 384768
Story category Covid, Research