Six distinct types of coronavirus have been identified by scientists in a breakthrough that promises to save lives by flagging the highest-risk patients. Analysis of thousands of cases by artificial intelligence software has revealed different “clusters” of symptoms and ranked them in order of severity. Headache and loss of smell are common to all six groupings, but the range of symptoms varies widely after that. Scientists at King’s College London (KCL) found that patients with the sixth type of Covid-19 are nearly 10 times more likely to end up needing breathing support than patients in the first group. This is significant because often patients only deteriorate to a critical stage several days after after showing symptoms. The new ranking system should flag up the highest-risk cases and give doctors the opportunity to intervene earlier.