Fig. 3: Lung pathology.

Calves (n = 7 to 9 biologically independent animals, see Table 1) received a single or two doses (1D or 2D, respectively) of ChAd155-RSV vaccine or placebo, followed by a short (4 weeks) or long (16 weeks) duration of immunity (short DOI or long DOI, respectively) and then a bovine RSV challenge. Placebo-S and placebo-L groups indicate the control groups subjected to the short-DOI and long-DOI regimens, respectively. On day post-challenge (dpc) 12/13 animals were subjected to necropsy. Macroscopic analysis of the consolidated lung areas (CLAs; a–c) and sums of lung pathology scores determined by microscopic analysis of the lung pathological changes (d–f) are presented for the study groups indicated in the keys above the graphs. Sums of lung pathological scores were derived by addition of the scores for alveolitis, interstitial pneumonia, peribronchitis and bronchitis per individual animal. Data are presented as means ± 95% confidence intervals. Each symbol represents an individual animal. Open symbols in c, f indicate animals that were pre-terminated or found dead on dpc 7/8. Vaccine groups were compared by two-sided t tests with the respective control groups using one-way ANOVA for CLAs and histopathology score sums with treatment as fixed effect and the appropriate variance assumption. Significant differences are indicated by asterisks (**P ≤ 0.01; ***P ≤ 0.001). Source data and statistical analyses with exact P values are provided as a Source data and Supplementary Data 1 and 2, respectively.