Cover photograph (Copyright © 2013, American Society for Microbiology. All Rights Reserved.): Scanning emulsion microscopy image of T84-cell monolayer infected with the Shiga toxin type 2 (Stx2)-producing Escherichia coli O104:H4 strain C227-11, which was isolated in the 2011 German outbreak. Cells were infected with O104:H4 bacteria for 3 h and then were washed and fixed with 4% paraformaldehyde. Slides were stained with Hoechst 33342 to visualize cell nuclei and bacterial cells (blue), with Phalloidin 654 to visualize actin (pink), and with an anti-Stx2 monoclonal antibody (11E10) followed by secondary donkey anti-mouse antibody conjugated to Alexa Fluor 488 to stain Stx2 (green). Samples were imaged using a Zeiss Elyra structured illumination microscope. Magnification, ×63. (Photo courtesy of Ninell Pollas Mortensen, Oak Ridge National Laboratory, Oak Ridge, TN, and Nadia Boisen, University of Virginia School of Medicine, Charlottesville, VA.) (See related article on p. 1562.)