1 Institute of Virology, National Reference Center for Papilloma-and Polyomaviruses, University of Cologne, 50935 Cologne, Germany. Electronic address: ulrike.wieland@uni-koeln.de.
2 Department of Dermatology, Venereology, and Allergology, Helios St Elisabeth Hospital Oberhausen, University Witten-Herdecke, Oberhausen, Germany.