Omicron: what do we know about the new Covid variant?

Scientists are racing to establish the variant's transmissibility, effect on immune system and chance of hospitalisation or death

Three major issues will determine the magnitude of the impact of the new Omicron variant of the Covid virus will have on the nation and the rest of the planet. What is the transmissibility of this new Covid variant? How good is it at evading the antibodies and T-cells that make up a person's immune defences? What are the chances it will trigger severe illness that could lead to the hospitalisation, and possibly death, of an infected person?

Scientists are struggling to find definitive answers to these critically important questions, although evidence already suggests Omicron has the potential to cause serious disruption. The situation is very finely tuned and could go in many different directions," says Prof Rowland Kao of Edinburgh University.