1 Institute for Hygiene and Microbiology, Julius-Maximilians-University Würzburg, Josef-Schneider-Str. 2/E1, 97080, Würzburg, Germany. okurzai@hygiene.uni-wuerzburg.de.
2 Institute for Hygiene and Microbiology, Julius-Maximilians-University Würzburg, Josef-Schneider-Str. 2/E1, 97080, Würzburg, Germany.