By Ryan Merrifield The new Covid wave “could be bigger than anything we’ve seen before” and we should consider wearing masks again, one expert is warning. The latest data from COG-UK shows the JN.1 variant now makes up 65% of all cases in the UK. The mutation – an offshoot of Omicron \- is highly contagious and infections could surge further with children going back to school this week, and people mixing more in the post-Christmas period. Added to that is the increase in flu numbers, already putting strain on the NHS. Professor Peter Openshaw, a virus expert at Imperial College London, is warn…