<p>Mice were immunized twice, three weeks apart, with MVA vectors and challenged three weeks later with (<b>A and B</b>) 42 LD<sub>50</sub> of H5N1 VN1203, (<b>C</b>) 32 LD<sub>50</sub> of mouse-adapted H9N2 HK/G9 or (<b>D</b>) 16 LD<sub>50</sub> of H7N1 RO/34. (<b>B</b>) Primed mice were infected intranasally with 100 TCID<sub>50</sub> H1N1pdm09 virus, six weeks before immunization. Animals were monitored for 14 days after challenge. Shown are the cumulative mean symptom scores whereby ruffled fur, curved posture, apathy and death were scored as 1, 2, 3 and 4, respectively.</p
