9/21/2016 Learning Objectives Food 1.Use basic biochemical characteristics to identify Bacillus cereus 2.Begin to appreciate the fluidity of bacterial nomenclature and etiology Chapter 8 AN INTRODUCTION 3.Understand what conditions in foods favor the growth of B.cereus Bacillus cereus 4.Recognize,from symptoms and time of onset,a case of foodborne illness caused by B.cereus 5.Choose appropriate interventions to prevent B. cereus from causing foodborne illness 6.Identify environmental sources of B.cereus 7.Understand the role of spores and toxins in causing foodborne illness Virginia Outbreak Virginia Outbreak ·July21,1993 B.cereus was isolated at >105/gram of Two day-care centers in Virginia vomit from one child ·Catered lunch B.cereus was isolated at >106 gram of Chicken-fried rice was implicated leftover chicken One-third of those who ate the rice Rice was cooked the night before,cooled became ill within 2 hours with nausea at room temperature,and refrigerated abdominal cramps,and diarrhea Next morning,rice and chicken were fried Median time for recovery was 4 hours with oil,delivered to the day care center, None of those who did not eat the rice held without refrigeration,and served became ill without heating 9/21/2016 1 Chapter 8 Bacillus cereus Learning Objectives 1. Use basic biochemical characteristics to identify Bacillus cereus 2. Begin to appreciate the fluidity of bacterial nomenclature and etiology 3. Understand what conditions in foods favor the growth of B. cereus 4. Recognize, from symptoms and time of onset, a case of foodborne illness caused by B. cereus 5. Choose appropriate interventions to prevent B. cereus from causing foodborne illness 6. Identify environmental sources of B. cereus 7. Understand the role of spores and toxins in causing foodborne illness Virginia Outbreak • July 21, 1993 • Two day-care centers in Virginia • Catered lunch • Chicken-fried rice was implicated • One-third of those who ate the rice became ill within 2 hours with nausea, abdominal cramps, and diarrhea • Median time for recovery was 4 hours • None of those who did not eat the rice became ill Virginia Outbreak • B. cereus was isolated at >105 / gram of vomit from one child • B. cereus was isolated at >106 / gram of leftover chicken • Rice was cooked the night before, cooled at room temperature, and refrigerated • Next morning, rice and chicken were fried with oil, delivered to the day care center, held without refrigeration, and served without heating