shigella

Bacteria are living things that have only one cell. Under a microscope, they look like balls, rods, or spirals. They are so small that a line of 1,000 could fit across a pencil eraser. Most types of don't make you sick. Many types are helpful. Some of them help to digest food, destroy disease-causing cells, and give the body needed vitamins. Bacteria are also used in making healthy foods like yogurt and cheese.

But infectious bacteria can make you ill. They reproduce quickly in your body. Many give off chemicals called toxins, which can damage tissue and make you sick. Examples of bacteria that cause infections include Streptococcus, Staphylococcus, and E. coli.

Antibiotics are the usual treatment. When you take antibiotics, follow the directions carefully. Each time you take antibiotics, you increase the chances that bacteria in your body will learn to resist them causing antibiotic resistance. Later, you could get or spread an infection that those antibiotics cannot cure.

NIH: National Institute of Allergy and Infectious Diseases

Each year, around 48 million people in the United States get sick from contaminated food. Common causes include bacteria and viruses. Less often, the cause may be a parasite or a harmful chemical, such as a high amount of pesticides. Symptoms of foodborne illness depend on the cause. They can be mild or serious. They usually include:

• Upset stomach
• Abdominal cramps
• Nausea and vomiting
• Diarrhea
• Fever
• Dehydration

Most foodborne illnesses are acute. This means that they happen suddenly and last a short time.

It takes several steps to get food from the farm or fishery to your dining table. Contamination can happen during any of these steps. For example, it can happen to:

• Raw meat during slaughter
• Fruits and vegetables when they are growing or when they are processed
• Refrigerated foods when they are left on a loading dock in warm weather

But it can also happen in your kitchen if you leave food out for more than 2 hours at room temperature. Handling food safely can help prevent foodborne illnesses.

Most people with foodborne illness get better on their own. It is important to replace lost fluids and electrolytes to prevent dehydration. If your health care provider can diagnose the specific cause, you may get medicines such as antibiotics to treat it. For more serious illness, you may need treatment at a hospital.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases