Fluorescent virus precipitin test.

A fluorescent virus precipitin test (FVPT) for the serologic identification of small particulate antigens such as viruses has been described. The test has several advantageous characteristics: (a) It is probably as sensitive as any serologic test (i.e., aggregates with dimensions of 0.2 mum are detectable; therefore, complexes containing as few as three large viruses would give a positive test). (b) Cultivation of the virus is not required. (c) Since an indirect test can be used, only a single fluorescent conjugate is needed to permit the detection of a number of viruses. (d) The indirect test can be used to detect antiviral antibody. (e) The FVPT is rapid and reliable. (f) Its simplicity should enhance its general acceptance and application.