1 National Reference Centre for Streptococcus pneumoniae, University Hospitals Leuven, Campus Gasthuisberg, 3000 Leuven, Belgium. Electronic address: stefanie.desmet@uzleuven.be.
2 Department of Microbiology and Immunology, Katholieke Universiteit Leuven, Leuven, Belgium.
3 National Reference Centre for Streptococcus pneumoniae, University Hospitals Leuven, Campus Gasthuisberg, 3000 Leuven, Belgium.