Use of anthocyanin-anionic polysaccharide complex for preventing or treating influenza virus A infection

A method for treating a disease caused by influenza virus A infection, the method comprising administering to a mammal having an influenza virus A disease a therapeutically effective amount of a pharmaceutical composition comprising an anthocyanin-anionic polysaccharide complex as an active ingredient, wherein the weight ratio of anthocyanin to anionic polysaccharide in the complex is 1:1 to 1:100,

• wherein the anthocyanin is derived from aronia and the anionic polysaccharide is an alginic acid, and
• wherein the anthocyanin is cyanidin 3-galactoside, cyanidin 3-glucoside, cyanidin 3-arabinoside, cyanidin 3-xyloside, or combinations thereof,
• wherein the anthocyanin-anionic polysaccharide complex provides increased antiviral efficacy against influenza virus A compared to the anthocyanin alone, anionic polysaccharide alone, and compared to antiviral efficacy of the anthocyanin-anionic polysaccharide complex against influenza virus B.