Comparison of direct immunofluorescent staining of clinical specimens for respiratory virus antigens with conventional isolation techniques

Staining of clinical respiratory specimens obtained by nasopharyngeal and throat swabs with direct fluorescein isothiocyanate-conjugated antisera to para-influenza virus types 1, 2, and 3, influenza A virus, respiratory syncytial virus, adenovirus, mumps virus, and measles virus was compared with isolation procedures in routine tissue culture systems. Direct staining of clinical specimens with the commercially available conjugated offered a rapid means of diagnosing respiratory infections on a routine clinical basis when used in conjunction with isolation in tissue culture systems. Of 292 patients who were culture positive for these viruses, 259 were diagnosed by detection of the viral antigen in clinical specimens by direct immunofluorescence. No specimens that subsequently yielded a different respiratory virus by culture were positive by the direct immunofluorescence method. Use of selected antisera based on clinical history of the patient reduced the cost of rapid viral diagnosis.