Background A heptavalent pneumococcal protein conjugate vaccine (PCV-7) was introduced in the routine vaccination schedule in The Netherlands in 2006. Data of invasive Streptococcus pneumoniae infections and serotype distribution in The Netherlands are incomplete as these are, in contrast to meningitis, not included in national surveillance. We analysed retrospectively serotype distribution and outcome in 33 paediatric intensive care unit (PICU) patients with invasive pneumococcal disease before the introduction of routine PCV-7 vaccination.
Methods The medical records of patients with culture confirmed invasive pneumococcal disease requiring admission to the PICU over a 5-year period (2001–6) were reviewed. Clinical and laboratory data were collected using a standard form.
Results The majority of infections (64%) were observed under 2 years. The overall mortality was 33% whereas it was 64% under the age of 2 years. Of surviving patients 30% showed severe neurological sequelae. Underlying conditions were observed in 36%. All patients with asplenia or splenic dysfunction presented with severe septic shock and rapidly fatal outcome. In 26 of the 33 isolated pneumococcal strains the serotype could be identified: 35% of these serotypes were not included in the seven valent pneumococcal vaccine. No penicillin or macrolide-resistant S pneumoniae were isolated.
Conclusion In our pre-standard PCV PICU population 35% of patients would not have benefited from PCV-7 vaccination. More effective vaccination strategies are indicated in high-risk patients.