1. Dr. Stefanie Papp, Katharina Kimmerl, Jacob Gatz, Prof. Dr. Roland Grunow, and Dr. Oliver Kaspari are with the Centre for Biological Threats and Special Pathogens, Highly Pathogenic Microorganisms (ZBS 2); Dr. Michael Laue is with the Centre for Biological Threats and Special Pathogens, Advanced Light and Electron Microscopy (ZBS 4); all are with the Robert Koch Institute, Berlin, Germany.