Protection of IFNAR^−/− mice immunized with the cell culture based vaccine against CCHF virus Turkey-Kelkit06 strain challenge.

<p>Groups of 6 IFNAR^−/− mice were immunized three times at three weeks intervals with 5, 20, or 40 μg of the cell culture based vaccine. The control group of IFNAR^−/− mice (n = 6) was mock immunized with phosphate buffered solution (PBS). All animals were challenged with 1,000 PPFU (400 LD50) of CCHF virus Turkey- Kelkit06 strain two weeks after the last immunization. The mice were monitored twice daily for the cumulative mean symptom scores (A), the daily variations in weight as percentages compared to before the virus challenge (B), body temperature (C), and geometric mean time to death and survival (D). The animals were monitored for three weeks after the challenge. The standard deviations are shown as error bars.