The expert: That means the new vaccine message

The pharmaceutical company Moderna is the latest in a series to state that their vaccine against the coronavirus works.

In the past, Pfizer and Russia's independent investment fund have also announced that they have developed vaccines that have at least 90 percent effectiveness against the virus.

But what does the companies' new message really mean?

So far, their data has not been reviewed through a so-called "peer review", which means that the information so far only comes from the companies themselves.

Companies have contacted the Medical Products Agency

Charlotta Bergquist is the vaccine coordinator at the Medical Products Agency and she says that some of the companies have already contacted them.

- They send in their study reports which we will review and then decide whether a vaccine should be approved or not.

What does it mean that a vaccine is 90 percent effective, how should we interpret the companies' positive message and how safe will a vaccine be?

See Charlotta Bergquist answer that in the player above.