Coronavirus: Your vaccine questions answered by an expert
The UK begins a mass Covid-19 vaccination programme on Tuesday, beginning with the elderly, health workers, and carers. The country was the first to approve use of the Pfizer/BioNTech vaccine.
Is the vaccine safe for people with chronic illnesses? What demographics was the vaccine tested on? Dr Penny Ward, a professor of pharmaceutical medicine, answers members of the public's questions about the Covid-19 vaccine.
More of your questions about the vaccine are answered here.
Video produced by Michael Cowan
Graphics by Mel Lou