Joint research of the Pharmaceutical Sciences Faculty of Kyushu University and Food Science Department of Campinas University in 2008 investigated the antiviral efficacy of propolis extracts against influenza viruses (flu) under in vivo and in vitro conditions. The experimental design involved oral feeding of virus-infected mice with propolis extracts at different doses of 0.4 mg/kg, 2 mg/kg ve 10 mg/kg three times during seven days, while the control group received none. The scientists reported a faster recovery in the symptoms in mice treated with propolis depending on the increase in dosage. The observed positive effects on body weight and the survival times of infected mice were related to the antiviral activity of propolis, blocking the growth of the virus. Moreover, in vivo experiments demonstrated the hindrance of virus infection in the lungs by propolis. The scientists concluded that regular propolis intake ameliorates influenza (flu) symptoms, and it can be a possible candidate for an anti-influenza dietary supplement for humans.
Reference:Shimizu T, Hino A, Tsutsumi A, Park Y, Watanabe W, Kurokawa M, 2008, “Anti-influenza virus activity of propolis in vitro and its efficacy against influenza infection in mice,” Antiviral Chemistry & Chemotherapy 19:7–1