Veterinärmedizinische Aspekte der Infektionen durch enterohämorrhagische E.-coli-Stämme (EHEC)

Enterohaemorrhagic Escherichia coli (EHEC) strains can cause severe foodborne human diseases and even fatalities. They are a subgroup of verocytotoxin producing E. colis (VTEC) with EHEC expressing additional virulence factors. Most strains produce the adhesion factor “intimin”. The prototype of this pathogroup is the E. coli serovar O157:H7, which is predominant worldwide. Ruminants are considered as the primary reservoir. High prevalence rates are reported from nearly all EU countries. The primary circle of infection and contamination of cattle livestocks and the surroundings by living and non-living vectors can hardly be broken through. Pre-slaughter washing of cattle as well as decontamination procedures of carcasses were not able to prevent increase of O157 diseases in the USA. To reduce the EHEC hazard the trimming of carcasses can be recommended. Although raw food of animal as well as of plant origin may be an important source of EHEC infection, the direct contact with animals and transmissions from person to person have to be considered important infection routes.