Food safety and food poisoning outbreaks

talk in general terms about the problems of food poisoning outbreaks including measures that are currently in place to control risks (eg HACCP, GMP, washing of agricultural produce with chlorinated water / chlorine dioxide / other methods, good hygiene practices) and point out that with all of these measures, we are still seeing a lot of potentially very serious outbreaks eg the recent one in Germany.
also a small talk about small E. coli O157 and salmonella epidemiology ie incidence, foods associated with it etc..mention very briefly some of the key features of virulence in this organisms.