Genetic and biological properties of H7N9 avian influenza viruses detected after application of the H7N9 poultry vaccine in China
Fig 5
Protective efficacy of H5/H7-Re2 trivalent inactivated vaccine against challenge with different H7N9 viruses in chickens.
HI antibody titers (A-E), virus shedding titers (F-J), and survival patterns (K-O) of chickens challenged with the H7N9 highly pathogenic viruses CK/GX/SD098/17 (A, F, and K), CK/SX/SD006/18 (B, G, and L), PCK/LN/SD004/19 (C, H, and M), CK/IM/SD010/19 (D, I, and N), and CK/LN/SD25/19 (E, J, and O). The dashed lines shown in A-E show the cutoff value for seroconversion and those in F-J show the lower limit of virus detection. Virus titers shown in F-J are the means from the birds that survived. A value of 0.5 was assigned to virus shedding-negative birds for statistical purposes. The asterisks indicate that the bird(s) died before that day, and therefore virus shedding data were not available for statistical analysis. All of the chickens in these control groups died within 5 days of challenge. The letter “a” indicates p < 0.001 compared with the corresponding titers of the control birds.