STX2 and infection: Whereas during 2000–2009, O26:H11-ST29 harboring stx1a/stx2a or stx2a alone was detected in 11.3% of human infections due to STEC in Switzerland (Käppeli et al., 2011a; Zweifel et al., 2013), in the time span 2000–2014 only one such strain (1.1% of all isolates) was isolated, suggesting a decline of the highly virulent German clone in Switzerland over the last decade.