One of the biggest unknowns in the pandemic was whether or not vaccination would stop you getting infected with coronavirus, or just stop you getting sick.

It sounds like much the same thing, but the difference is actually huge. Stopping infection means you don't have the virus at all, and thus won't go on to infect others.

A study in the journal The Lancet has looked at both the Pfizer and AstraZeneca vaccines and found that they do indeed stop infection, which is great news - but sadly not all the time.

That's on today's Coronacast.

Also on today's show:

* If you are a blood donor and have been vaccinated, will the antibodies you have developed help the recipient of your blood?

* I've already received the first dose of the AstraZeneca vaccine. Is it safe for me to swap over and get Pfizer if it is available to me? I'm in category 1B as I'm a health worker.