Elucidating antiviral activity of Curcuma longa against H9 N2 influenza virus using embryonated chicken egg model

Curcumin is a potent antimicrobial herb used traditionally as a spice in culinary. This study was designed to evaluate the antiviral effects of curcuma longa extract against H9 influenza virus. A total of 60 embryonated eggs were equally divided into 5 groups with 12 eggs in each group. Group 1 (G1) served as uninfected negative control. Whereas Group 2 (G2) was kept as positive control infected with known virus @ 0.2 ml with 10-9.3 EID50. Group 3 (G3) was offered Curcuma longa @ 0.2 mg/0.2 ml and H9N2 virus (@ 0.2 ml with 10-9.3 EID50. Similarly, Group 4 (G4) was inoculated with extract of Curcuma longa @ 0.2 mg/0.2 ml per egg, whereas Group 5 (G5) was given Ribazole @ 0.2 ml/ egg. The crude extract and virus were administered on the 15th day of incubation and were checked after every 24 hours up to 96th hour post inoculation by random selection of 3 eggs. Death and survival rate were noted in all groups. Gross and histopathological lesions were also observed. Results revealed that Curcuma longa extract had significantly (p<0.05) reduced the mortality rate of embryos infected with H9N2 virus. In G3, increased lymphocytes and mild fatty changes were seen in liver. Whereas, mature RBCs, plasma cells and some lymphoblast's were observed in Spleen. Similarly, the bursa follicles were with lymphocytic aggregation. The G4 (Curcuma longa) and G5 (Ribazole) were with maximum embryo survival after 48 and 72 h post inoculation. This study revealed potential antiviral activity of Curcuma longa against H9N2 influenza viruses and can be opted as alternative to antibiotics and antiviral drugs to minimize the antimicrobial resistance in human and animal population.