Bad Bug Book (Second Edition)
Pathogenic Microorganism Handbook
Metadata Updated: April 24, 2018

Introduction for Consumers: A Snapshot Each chapter in this book is about a pathogen – a bacterium, virus, or parasite – or natural toxin that can contaminate food and cause illness. The book was prepared by the Food and Drug Administration (FDA) and contains scientific and technical information about the major pathogens that cause these kinds of illnesses. A separate “consumer box” in each chapter provides non?technical information, in everyday language. The boxes describe plainly what can make you sick and, more important, how to prevent it. Most foodborne illnesses, while unpleasant, go away by themselves and don’t have lasting effects. But you’ll read about some pathogens that can be more serious, have long?lasting effects, or cause death. To put these pathogens in perspective, think about how many different foods and how many times you eat each day, all year, without getting sick from the food. The FDA and other Federal agencies work together and with the food industry to make the U.S. food supply one of the safest in the world. You also play a part in the safety of what you eat. When you read the consumer boxes, you’ll see that different pathogens can be risky in different ways, and that a safety step that’s effective against one might not be as effective against another. So what should you do? The answer is to follow some simple steps that, together, lower the risk from most pathogens. ? Washing your hands before and after handling food, and in between handling different foods, is one of the most important steps you can take. Do the same with equipment, utensils, and countertops. ? Wash raw fruits and vegetables under running water. These nutritious foods usually are safe, as you probably know from the many times you’ve eaten them, but wash them just in case they’ve somehow become contaminated. For the most part, the less of a pathogen on a food – if any – the less chance that it can make you sick. ? Cooking food to proper temperatures kills most bacteria, including Salmonella, Listeria, and the kinds of E. coli that cause illness, and parasites. ? Keep any pathogens that could be on raw, unwashed foods from spreading by keeping raw and cooked foods separate. Keep them in different containers, and don’t use the same equipment on them, unless the equipment is washed properly in between. Treat countertops the same way. ? Refrigerate food at 40°F as soon as possible after it’s cooked. Remember, the less of a pathogen there is in a food, the less chance that it can make you sick. Proper refrigeration keeps most types of bacteria from growing to numbers that can cause illness (although if a food already has high numbers of bacteria when it’s put in the refrigerator, it could still cause illness). Here are a few examples of why following all of these steps is important. Some types of bacteria form spores that aren’t killed by cooking. Spores are a survival mode in which those bacteria make an inactive form that can live without nutrition and that develops very tough protection against the outside world. After cooking, the spores may change and grow into bacteria, when the food cools down. Refrigerating food quickly after cooking can help keep the bacteria from multiplying. On the other hand, cooking does kill most harmful bacteria. Cooking is especially important when a pathogen is hard to wash off of a particular kind of food, or if a bacterium can grow at refrigerator temperatures, as is true of Listeria monocytogenes and Yersinia enterocolitica. As you read about the differences among the pathogens, remember that there’s a common theme: following all the safety steps above can help protect you. The exceptions are toxins, such as the poisons in some mushrooms and a few kinds of fish and shellfish. Cooking, freezing, and washing won’t necessarily destroy toxins. Avoiding them is your best protection, as you’ll see when you read the chapters.