Direct and indirect effects of rotavirus vaccination upon childhood hospitalizations in 3 US counties, 2006-2009

Abstract

Background. Routine rotavirus vaccination of US infants began in 2006. We conducted active, population-based surveillance for rotavirus gastroenteritis hospitalizations in 3 US counties to assess vaccine impact.Methods.Children <36 months old hospitalized with diarrhea and/or vomiting were enrolled from January through June each year during the period 2006-2009 and tested for rotavirus. Age-stratified rates of hospitalization for rotavirus infection were compared with corresponding vaccination coverage among a control group of children with acute respiratory illness. To assess direct and indirect benefits, vaccination coverage rates in the control group were multiplied by vaccine effectiveness estimates to calculate expected reductions in the rate of hospitalization for rotavirus infection. Rotavirus serotypes were compared across years.Results.Compared with 2006, a significant reduction in rates of hospitalization for rotavirus infection (P