Figure 2.

Cumulative incidence of rotavirus hospitalization before and after the introduction of rotavirus vaccine, by season of birth (per 10,000 person-years; top row) and even/odd calendar year of birth (per 10,000 births; bottom row), among children under 5 years of age, United States, 2001–2014. Rotavirus vaccine was introduced in late 2006, so we considered children born in 2007 and later as having been born during the postvaccination period. Note the differences in scale between the pre- and postvaccination periods. A) Children born prior to vaccine introduction (2002–2006); B) children born after vaccine introduction (2007–2014); C) children born prior to vaccine introduction, by even/odd calendar year of birth; D) children born after vaccine introduction, by even/odd calendar year of birth. Bars, 95% confidence intervals.