ALBAWABA Donald Triplett, who was the first person to be diagnosed with autism, died last week in of Forest, Mississippi, age 89, the cause of death was cancer. A group of doctors diagnosed Triplett in the year 1943 as having a cognitive neurological disorder called "autism," and he was 10 years old at that time. Donald Triplett, who as a child was “Case 1” in the history of autism diagnosis ...