Clostridium botulinum are rod-shaped bacteria (also called C. botulinum). They are anaerobic, meaning they live and grow in low oxygen conditions. The bacteria form protective spores when conditions for survival are poor. The spore has a hard protective coating that encases the key parts of the bacterium and has layers of protective membranes. Within these membranes and the hard coating, the dormant bacterium is able to survive for years. C. botulinum is responsible for a disease called botulism.

"Campylobacter" bacteria are the second most frequently reported cause of foodborne illness. A comprehensive farm-to-table approach to food safety is necessary in order to reduce campylobacteriosis. Farmers, industry, food inspectors, retailers, food service workers, and consumers are each critical links in the food safety chain. This document answers common questions about the bacteria "Campylobacter," describes how the Food Safety and Inspection Service (FSIS) of the U.S. Department of Agriculture (USDA) is addressing the problems of "Campylobacter" contamination on meat and poultry products, and offers guidelines for safe food handling to prevent bacteria, such as "Campylobacter," from causing illness.

Escherichia coli (abbreviated as E. coli) are a large and diverse group of bacteria. Although most strains of E. coli are harmless, others can make you sick. E. coli O157:H7 is a kind of E. coli that can cause disease by making a toxin called Shiga toxin. Often when you hear news reports about outbreaks of E. coli infections, they are talking about E. coli O157:H7.

Listeriosis is a serious infection usually caused by eating food contaminated with the bacterium Listeria monocytogenes. An estimated 1,600 people get listeriosis each year, and about 260 die. The infection is most likely to sicken pregnant women and their newborns, adults aged 65 or older, and people with weakened immune systems.

Some molds cause allergic reactions and respiratory problems. And a few molds, in the right conditions, produce "mycotoxins," poisonous substances that can make people sick. When you see mold on food, is it safe to cut off the moldy part and use the rest? To find the answer to that question, delve beneath the surface of food to where molds take root.

Salmonella bacteria are the most frequently reported cause of foodborne illness. The Salmonella family includes over 2,300 serotypes of bacteria which are one-celled organisms too small to be seen without a microscope. Two types, Salmonella Enteritidis and Salmonella Typhimurium are the most common in the United States and account for half of all human infections.

Parasites may be present in food or in water and can be identified as causes of foodborne or waterborne illness in the United States. They range in size, from tiny single-celled organisms to worms visible to the naked eye. Their lifecycle may also vary. While some parasites use a permanent host, others go through a series of developmental phases using different animal or human hosts. The illnesses they can cause range from mild discomfort to debilitating illness and possibly death.