Why can Covid vaccines cause side effects?

Coronavirus vaccines help protect people from getting seriously ill if they come into contact with the disease. It's normal to experience some mild side effects, such as a headache or a raised temperature - but a vaccine can't give you the virus.

But how do they work? And will a vaccine make you feel unwell?

Voice: Marnie Chesterton

Video journalist: Jennifer Green

Graphics: We Are Covert

With thanks to virologist Prof Jonathan Ball, University of Nottingham.

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