The federal Centers for Disease Control and Prevention is warning doctors about a serious rare inflammatory condition in children linked with the coronavirus. In an alert issued Thursday, the CDC called the condition multisystem inflammatory syndrome in children. The agency’s case definition includes current or recent COVID-19 infection or exposure to the virus, a fever of at least 100.4 for at least 24 hours, severe illness requiring hospitalization, inflammatory markers in blood tests, and evidence of problems affecting at least two organs that could include the heart, kidneys, lungs, skin or other nervous system. The name and definition are similar to those used in Europe, where the condition was first reported several weeks ago.