Impact of rotavirus vaccination in regions with low and moderate vaccine uptake in Germany

In Germany, routine RV-vaccination is not adopted into the national immunization schedule as of 2012. Because RV-vaccines were already on the market since 2006, in 2010 a moderate (58%) and low (22%) vaccine uptake was observed in the 5 eastern federal states (EFS) and the 11 western federal states (WFS), respectively. To assess the impact of RV-vaccination, we compared the incidence rates (IR) of RV-related hospitalizations before (2004‒2006) and in seasons after (2008/09-2010/11) RV-vaccine introduction in Germany by utilizing data from the national mandatory disease reporting system. In the EFS, the IR was significantly reduced in age-groups < 18 mo in 2008/09 and in age-groups < 24 mo in 2009/10-2010/11. In the WFS an IR-reduction was observed only in age-groups < 12 mo in 2008/09 and in age-groups < 18 mo in 2009/10-2010/11. Overall IR-reduction in age-groups < 24 mo comparing 2008-11 with 2004-06 was 36% and 25% in EFS and WFS, respectively. In addition, we computed IR-ratios (IRR) in the seasons after mid-2006 with negative binomial regression. The effect of vaccination was independent from the geographic region. Vaccination was associated with a significant reduction in RV-related hospitalizations in the age-groups 6-23 mo. Most prominently, vaccination of 50% of infants led to an estimated decrease in age group 6-11 mo by 42%. No significant reduction was observed in age-groups ≥ 24 mo. In conclusion, in the German setting with low to moderate vaccine uptake, RV-related hospitalization incidence decreased substantially depending on the achieved vaccination coverage, but only in the first two years of life.