Effects of traditional oriental medicine on influenza virus infection—Protective effect of Mao-Bushi-Saishin-To (MBST, Ma-Huang-Fu-Zi-Xin-Tang), a traditional oriental medicine, on influenza virus infection in aged mice

Abstract Mao-Bushi-Saishin-To (MBST, Ma-Huang-Fu-Zi-Xin-Tang), a traditional oriental herbal medicine, is frequently used for the treatment of the common cold in Japan. MBST shows particularly good results in elderly patients. We examined the effects of post-infection MBST administration on influenza in aged mice. At 3 and 6 days after infection and MBST administration, the virus was isolated from the lungs of all mice in all groups. However, the average virus quantity correlated inversely with the MBST dose in the 0, 20 and 200 mg/kg administration groups. In addition, the number of mice in each group from which virus was isolated by pharyngo-oral swab decreased in order in the 0, 20 and 200 mg/kg groups. These results show that MBST suppresses the proliferation of influenza virus in the lungs and suppresses the discharge of the virus from the upper respiratory tract. From these results, it became clear that MBST was effective in controlling the infectious expansion of the influenza virus.