Adaptation of the influenza neuraminidase and neuraminidase-inhibition assays to the microtitrator system.

A micro-method based on Warren's colour reaction has been developed for influenza neuraminidase and neuraminidase-inhibition assays. Extraction with butanol is omitted and the assay is performed in wells of special plexiglass trays, where the reaction mixon and compared to controls in the same tray. The micro-assay, being inexpensive, time-saving and easy to perform even in poorly equipped laboratories, is suitable for large-scale serological screening and identification of the neuraminidase antigen of isolates.