Large-scale testing of a potential covid-19 vaccine is underway in many parts of the world.
Eleven vaccine candidates are in so-called phase 3 studies - the last testing stage before any approval.
- It is only when the phase 3 studies are completed that it is known whether the vaccine really works, that is, that they either protect against infection, disease or death, says Matti Sällberg.
So far, only Astra Zeneca and Pfizer-Biontech have started an approval procedure at the Medical Products Agency.
They have been granted an ongoing evaluation, which means that the data is reviewed as it is clear.
- We are still waiting for the large clinical studies, so it is not really possible to say when it will be ready yet, says Charlotta Bergquist, vaccine coordinator at the Medical Products Agency.
In the video, Matti Sällberg goes through how a vaccine against covid-19 goes and when vaccination can start here in Sweden.