A small number of children in Britain have fallen sick with a mysterious syndrome that could be linked to the novel coronavirus. The Guardian reports top pediatric officials in England’s National Health Service have became so concerned about the symptoms that they have issued a written warning to doctors, alerting them to the existence of the syndrome. The children affected appear to have been hit by a form of toxic shock syndrome, with symptoms including a sore stomach and heart problems. Some have been left so unwell that they have had to be treated in intensive-care units. In a letter to doctors, NHS bosses said: “There is a growing concern that a SARS-CoV-2-related inflammatory syndrome is emerging in children in the U.K., or that there may be another, as yet unidentified, infectious pathogen associated with these cases.” It is not known if any children struck by the new syndrome have died, or exactly how many have fallen ill, but there appears to have only been a handful of cases.