Coloured 3D computed tomography scan of the heart of a child with Kawasaki disease. The condition, a form of vasculitis (blood vessel inflammation), has caused an aneurysm (yellow bulge, centre left) of the right coronary artery. Kawasaki disease is a rare condition that mainly affects children under five. The main symptoms are a fever, rash and oedema (swelling). Heart disease and aneurysms are a complication of the disease. It's cause is unknown. A Kawasaki-like disease has been linked to infection with the novel coronavirus SARS-CoV-2, the cause of Covid-19.