1. Department of Medical Microbiology, Meander Medical Centre, Amersfoort, the Netherlands
2. Public Health Service Region Utrecht, Zeist, the Netherlands
3. Centre for Infectious Diseases Control, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
4. Department of Surgery, Meander Medical Centre, Amersfoort, the Netherlands
5. Department of Intensive Care, Meander Medical Centre, Amersfoort, the Netherlands
6. Department of Medical Microbiology and the Netherlands Reference Laboratory for Bacterial Meningitis, Academic Medical Center, Amsterdam, the Netherlands