Immunofluorescence in diagnosis of measles infections in children.

Nasopharyngeal cells of 24 patients diagnosed as being in the prodromal phase or with established measles were examined by indirect immunofluorescence microscopy for the presence of measles antigen. Eighteen patients were positive for measles antigen by this technique. In ten of the 18 patients it was necessary to remove masking globulins from the antigen-containing cells prior to staining. Results obtained by immunofluorescence were supported by cytologic and serologic findings. No virus isolations were achieved. Immunofluorescence microscopy with elution of adherent globulins offers the most rapid and sensitive method for the laboratory diagnosis of measles.