The initial symptoms were thought to be Rubella, however the clinical features were different.
Patients exhibited no Koplik's spots, the course of the infection was shorter, and the skin lesions differed from Rubella.
Two physicians, Franklin A. Neva from the University of Pittsburgh, and Ilse J. Gorbach investigated the outbreak.
Through surveys sent to physicians, 18 cases were identified and specimens collected, 15 children and 3 adults.
After notifying area physicians, an additional 7 cases were identified in other parts of the city.