Efficiency of immunofluorescence for rapid detection of common respiratory viruses

Rapid immunofluorescence (FA) methods for the detection of common respiratory viruses were compared with culture results over a 3-year period to assess the relative efficiency of FA in a clinical laboratory setting. For respiratory syncytial virus, efficiencies were high (sensitivity, 90 to 95%; specificity, 92 to 95%). The sensitivity of FA for detection of parainfluenza virus type 1, parainfluenza virus type 3, influenza A virus, and adenoviruses ranged from 28 to 63%, but specificities for these viruses were uniformly 98 to 100%. The observations form a basis for consideration of selective reduction of routine culture procedures for specimens with initial positive rapid FA results; however, the possibility of dual viral infection in some situations must also be considered.