2/16/2016 Shigella in Foods Shigella in Foods Not associated with specific foods .Thus,routine testing for Shigella is not done Many cases the source of the food is unknown ·Common foods potato salad ·1983-1987 -chicken 54,453 cases reported and in only 38%was -tossed salad -shellfish the source of the etiological agent identified Establishments Shigella are often not recovered from food home schools Traditional methods test the final product, restaurant airlines which may be time-consuming camps sorority houses picnics military mess halls Shigella in Foods Survival and Growth in Foods Hazard Analysis and Critical Control Point pH plans identify points of the processing system that is most vulnerable to microbial Survives in media with a pH 2-3 for several hours contamination HACCP system may NOT detect Shigella Does not survive well in foods with low pH or stool samples not indigenous to the food product -1-6 days survival in citrus juices,wine collected and sent to market directly carbonated drinks (lettuce) 100 days in neutral foods such as introduced by food handlers butter when stored at 40C or frozen -contamination likely occurs between food processing and the consumer 2/16/2016 5 Shigella in Foods • Not associated with specific foods • Thus, routine testing for Shigella is not done • Common foods - potato salad - chicken - tossed salad - shellfish • Establishments home sch l oo s restaurant airlines camps sorority houses picnics military mess halls Shigella in Foods • Many cases the source of the food is unknown • 1983 – 1987 54,453 cases reported and in only 38% was the source of the etiological agent identified • Shigella are often not recovered from food • T diti l th d t t th fi l d t Traditional meth o ds test th e final pro duct, which may be time-consuming Shigella in Foods • Hazard Analysis and Critical Control Point p yp p g y lans identif y points of the processin g s ystem that is most vulnerable to microbial contamination • HACCP system may NOT detect Shigella - not indigenous to the food product - collected a nnm y d se nt to market directl y (lettuce) - introduced by food handlers - contamination likely occurs between food processing and the consumer Survival and Growth in Foods pH • Survives in media with a pH 2-3 for several hours • Does not survive well in foods with low pH or stool samples - 1-6 days survival in citrus juices, wine, carbonated drinks - 100 days in neutral foods such as butter when stored at 4 OC or frozen