US’s leading expert in infectious diseases, Anthony Fauci, says it should be known by the end of November or early December if a Covid-19 vaccine is safe and effective. A vaccine being developed by Oxford University and drug company AztraZeneca is considered the likeliest candidate to be used first. Speaking to the BBC, Fauci says the question is, once there is a vaccine, or more than one, how can it get to the people who need it the most, as quickly as possible.