Amanda Blake (Miss Kitty) died of AIds due to a blood transfusion years ago. I believe her case was one of the first high profile cases - she died much too early! James Arness was an awesome actor but also wonderful humble human being. They don't make them like him anymore. I remember begging my parents every Saturday night to stay up a little later than normal so I could watch Gunsmoke - what a treat!
I'm glad he didn't have to suffer and he was able to die peacefully in his sleep.