Epidemiology of Rotavirus Hospitalizations and Implications for Vaccination Strategies

Rotavirus (RV) is the leading cause of severe gastroenteritis (GE) in young children worldwide. Nearly every child gets infected with RV during the first 5 years of life. In the developed countries RV remains a common cause of physician consultations and hospital admissions, while in developing countries RV still accounts for nearly 500,000 deaths annually. Furthermore, hospital-acquired (nosocomial) RV infections cause significant additional disease burden in patients already hospitalized for other reasons. The availability of two licensed RV vaccines provides opportunities for prevention of rotavirus gastroenteritis (RVGE). In recent years RV vaccination has been implemented in the national immunization programs of several countries, but contradictory results on cost-effectiveness of RV vaccination limit widespread implementation, especially in Europe, where only few countries have adopted RV vaccination thus far. Hospitalization is the main driver of RV disease costs and prematurity, low birth weight (LBW) and underlying medical conditions have been associated with RV hospitalization and complications. Detailed evaluations of high-risk groups are lacking however, as are evaluations of targeted prevention strategies. This thesis aims to quantify RV disease burden caused by RV hospitalizations in developed countries and to identify risk factors for RV hospitalizations. This thesis further aims to identify an optimal vaccination strategy for RV in developed countries based on cost-effectiveness analysis of different vaccination strategies. In addition, this thesis aims to provide better insight in specific features of severe RVGE among susceptible populations such as premature and LBW infants, children with complex chronic conditions and immunocompromised patients. This thesis focuses on two countries: Canada and the Netherlands. In Canada, RV vaccination was still under consideration at the start of this thesis project, but has recently been implemented in several provinces. In the Netherlands, RV vaccination is currently considered for inclusion in the national immunization program but has not been implemented thus far