Impact of rotavirus vaccination on laboratory confirmed cases in Belgium.

Rotavirus vaccines were introduced in Belgium in 2006 and recommended in the universal schedule in January 2007. We measured the impact of rotavirus vaccination through an active laboratory-based surveillance system. In 2008, the number of laboratory confirmed rotavirus cases declined by 61.4% (95% CI 60.2-62.6%) compared to the 2005-2006 pre-vaccination period, with the highest decline in children<1 year (80.1%; 95% CI 78.7-81.4%). The rotavirus season was delayed compared to pre-vaccination seasons. Laboratory data provide a crude estimation of vaccination impact, but analysis of in-patient data will be needed to assess the impact on severe disease.