This product is prepared using influenza A and B virus strains recommended by the World Health Organization (WHO). The viruses are individually inoculated into embryonated chicken eggs, followed by cultivation, harvesting of the viral fluid, ultrafiltration concentration, viral disruption with centrifugation, purification, viral inactivation, and a second purification step to isolate hemagglutinin and neuraminidase. The final product contains no preservatives or antibiotics.