Background 
In Stockholm vaccination against rotavirus began in 2014. In this survey, we investigated changes in admission rates, etiology, age and characteristics for children 0-4 years of age admitted for gastroenteritis in our catchment area during eight seasons 2008-2016. 
Methods 
We included patients with a clinical diagnosis of gastroenteritis. Stool examinations for viruses were obtained in 80%. The frequency of underlying disease was about 26% for children infected with rotavirus and 39% for children infected with other viruses. 
Results 
The admission rate roughly halfed over the study period (figure). The reduction mainly corresponded to fewer rotavirus infections. There was no increase in other viruses. The median age of children infected with rotavirus increased from 13.7 to 18.5 months after vaccination was introduced. Interestingly, there were also fewer children aged 2-4 admitted. 8% of the children with rotavirus and 6% with other viruses developed a complication. Children infected with both noro- and rotavirus (5% of tested children) did not have a more severe disease than those with a single infection.
Conclusions 
Rotavirus vaccination reduced the number of children admitted for gastroenteritis. No replacement with other viruses was observed. There was a trend of reduced numbers of admitted children even before vaccination was started and also in older children not covered by the vaccination program.

02 / CHANGES OF THE INCIDENCE AND ETIOLOGY OF ACUTE GASTROENTERITIS AFTER THE INTRODUCTION OF ROTAVIRUS VACCINE IN STOCKHOLM, SWEDEN