Bacillus cereus is a rod-shaped aerobic organism that comes in two different forms, neither one of which is fun to have.
The one that causes diarrhea doesn’t cause vomiting, but the one that causes vomiting also causes diarrhea. The only good news is that either way, you get sick and get well fast: symptoms can start as soon as a half-hour after eating contaminated food, and they only last about 24 hours.
Beef, turkey, Mexican food, rice, potatoes, pasta, and shellfish have all been found to contain B. cereus, and anyone can get it. It’s widely distributed in soil, dust, and air, it’s carried by both humans and animals, and it’s impossible to avoid.
Since small quantities of the germ are harmless, the secret is to keep it from growing into larger quantities that can produce enough toxin to make you ill. You can’t really keep it out of food completely in the normal environment of a kitchen, but you can minimize its effects by thoroughly cooking food and refrigerating leftovers, especially cooked rice and other cereals.
Like S. aureus, B. cereus produces a poison that survives higher temperatures than the organism itself, the toxin can still be potent after it has been boiled.