1 Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center Rotterdam, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands.
2 Department of Medical Microbiology and Infectious Diseases, Erasmus MC University Medical Center Rotterdam, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands. Electronic address: m.vos@erasmusmc.nl.