Figure.

Timing of the increase in the incidence of non-vaccine serotypes relative to vaccine introduction in select studies that report serotype replacement. Light grey bars indicate pre-vaccine era, medium-grey bars indicate the period of vaccine introduction or low coverage, and the dark grey bars indicate widespread vaccination. The values represent the incidence in each year divided by the mean pre-PCV7 incidence, as indicated by the shaded bars and table 1. The data from the U.S., Spain, and England represent changes in all non-vaccine serotypes, and the data from the Norway study is just serotype 19A. There was no net increase among NVTs in Norway as of 2008.