Do I need a Covid-19 vaccine if I have antibodies?

Can I have a coronavirus vaccine if I am allergic to penicillin? What if I have asthma? Should I get the vaccine if I have antibodies? Can a person choose which vaccine they get?

Dr Gigi Gronvall, an immunologist at the Johns Hopkins Centre for Health Security in Maryland and Krutika Kuppalli, MD Assistant Professor of Medicine at the Medical University of South Carolina spoke to BBC World News’s Ben Bland to answer viewers’ questions.