Kawasaki disease is caused by an allergic reaction to a spider mite bite. The mites live in carpets and are disturbed when carpet cleaning occurs.
I saw that as well. It isn't clear if John Travolta's son, Jett, died as a result of Kawasaki disease or as a result of the hitting his head while having a seizure.
Kawasaki disease is also knows as mucocutaneous lympy node syndrome and is usually seen in children under 5 and is one of the two leading causes of acquired heart disease in the US. There are about 4000 cases diagnosed annually in the US.
The causes of it are unkown but it is believed to not to be contagious nor hereditary.
The symptoms of Kawasaki disease include fever,irritation and inflammation of the mouth, lips, and throat, sollen lymph glands in the neck, rash, and rdeness of the whites of the eyes, inflammation of the heart muscle (myocarditis) or the sac surrounding the heart (pericarditis).
Kawasaki Syndrome is pretty rare from what I've read. I'd never heard of it either, but they have some stuff on Kawasaki here at
http://www.medhelp.org/tags/show/18413/Kawasaki-Disease. There's a good overview in the health topics at
http://www.medhelp.org/medical-information/show/3886/Kawasaki-disease as well. Seems like it's mostly in Japan, but does happen in the States on occasion.