[Rapid diagnosis of respiratory viral disease by means of indirect immunofluorescence test].

Indirect immunofluorescence test was employed to detect respiratory virus antigens in pharyngeal secretions. Parainfluenza virus type 1-3 sera gave positive results in 19 out of 40 patients with acute respiratory infections tested, mainly among children affected by "viral croup". The reliability of the test for the rapid diagnosis of respiratory infections is discussed.