Fig. 4.

Effect of immune-interactions on vaccination impact. Comparison of pre- and post-vaccination dynamic behaviour and vaccine impact between the neutral model (grey) and models with 2 infections (cyan, A–D), antibody-dependent enhancement (ADE, green, E–H) and temporary cross-immunity (CI, orange, I–L). All scenarios include a catch-up campaign targeting a core group of individuals between 10 and 50 years of age with coverage 50%; routine vaccination coverage was 75% of individuals at 6 years of age. Incidence is presented per 100K individuals. (First column, A,E,I) Comparative timeseries between neutral and other models, showing the dynamics of total incidence. Solid lines represent 1-year averages and shaded areas show between-run variability based on 50 individual model runs. (Second column, B,F,J) Quantitative impact of vaccination as the percent change in incidence compared to pre-vaccination levels. (Third column, C,G,K) Quantitative impact of vaccination as the percent change in the age of first infection compared to pre-vaccination levels. (Fourth column, D,H,L) Quantitative impact of vaccination as the percent change in the age of secondary infection compared to pre-vaccination levels. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)