The purpose of this study is to assess the indirect effects of a pneumococcal conjugate vaccine administered to infants on vaccinees' elder non-vaccinated siblings aged 3 to 7 years.~This study includes a cross-sectional sampling of nasopharyngeal and oropharyngeal swabs in 2011 and a register-based follow-up study for invasive disease, hospital-diagnosed pneumonia, tympanostomy tube surgery and outpatient antimicrobial treatment.
The purpose of this study is to assess the indirect effects of a pneumococcal conjugate vaccine administered to infants on vaccinees' elder non-vaccinated siblings aged 3 to 7 years.