I had a cat die of this about 15 years ago. She was our only cat, and our vet said it is something that can lie dormant in them for years, before something triggers it. Highly contagious!
We were told to throw out all of her bedding, bowls, litterbox, toys etc., javex all areas she used in the house, and wait a minimum of 3 months before bringing another cat into the home.
My sympathies are with you ... it was a terrible way for a friend to go.
