“…The availability of influenza virus vaccines with adjuvants, such as those containing the oil-in-water emulsion MF59, has recently opened new, interesting perspectives for the prevention of the disease, not only in elderly subjects but also in adults belonging to well-recognized risk categories (3,4,17,24). Several studies of the elderly have demonstrated the higher immunogenicity of influenza virus vaccines with MF59 adjuvant than of split or subunit vaccines with no adjuvant (13,19,31,38,44).…”