Streptococcus pneumoniae is one of the most common causes of bacterial meningitis in children under 2 years of age. These infections are associated with high mortality and morbidity rates. In Europe, France is among the countries most affected by pneumococcal antibiotic resistance. In 2003, a pneumococcal conjugate vaccine was added to the vaccination schedule for children under 2 years of age with certain medical or family risk factors. Evaluating the surveillance of pneumococcal meningitis in children in France is an essential component of studying the epidemiological impact of this new vaccination. The objective of the study was to determine the incidence of pneumococcal meningitis in children prior to the implementation of vaccination and to assess the completeness of three different data sources. (Introduction)