The first well-documented case of autism was that of Donald Triplett, who is often referred to as "Case 1." He was first observed with symptoms around 1938, and his diagnosis was formally documented in 1943 by child psychiatrist Leo Kanner in a seminal paper titled "Autistic Disturbances of Affective Contact." This marked the beginning of autism being recognized as a distinct developmental disorder. Kanner's paper detailed the behaviors of 11 children, with Triplett being the first case described, laying the foundation for modern understanding of autism as a unique condition separate from other psychiatric disorders.
Earlier, the term "autism" had been used by Swiss psychiatrist Eugen Bleuler in 1911 to describe symptoms in schizophrenia, but it was Kanner's 1943 work that distinguished autism as its own diagnosis.
Thus, the first officially recognized case of autism dates back to 1943 with Donald Triplett's diagnosis by Leo Kanner.
