Dorothy Vaughan Mary Jackson Katherine Johnson

BBC Health

• Coronavirus: How do you vaccinate 7.7 billion people?
  Five challenges of distributing a Covid-19 vaccine to billions of people.
• Covid-19: Government adviser on vaccine announcement
  A government adviser says there's likely to be news soon, but stresses that a vaccine "mustn't be rushed" because it "has to be safe".
• Your coronavirus vaccine questions answered
  Prof Robin Shattock, head of Mucosal Infection and Immunity at Imperial College, answers viewers' questions.