Detection of air-borne Pasteurella tularensis using the fluorescent antibody technique.

Considerable research has been directed toward the development of rapid methods for the identification of air-borne microorganisms. The application of the fluorescent antibody technique (FAT) coupled with the impaction of contaminated air onto glass slides affords a rapid and specific method for the identification of air-borne Pasteurella tularensis. Early experiments presented problems of cross-reaction with organisms other than P. tularensis. These cross-reactions are eliminated by specific adsorption and proper dilution of the conjugate. A series of experiments conducted under rigidly controlled laboratory conditions indicates that fewer than ten viable P. tularensis per slide can be detected by this method. Time of impaction as well as the presence of large concentrations of other microorganisms did not alter this number. Calculations indicate that a concentration as low as one viable organism per 5 liters of air can be detected.