Giant Microbes Salmonella (Salmonella typhimurium) Petri Dish Which came first: the chicken, or the egg -- or the Salmonella bacteria? Children, parents and educators will enjoy using these educational plush toys to teach about hygiene, disease and the human body. Each microbe comes with a description of the disease it causes or function it performs. Use these fun, non-threatening toys to emphasize the importance of washing hands and preventing sickness in social settings. Surface wash, air dry. Each petri dish comes with 3 mini microbes.