What is food poisoning and how you can get it

Food poisoning is common, costly and preventable. The U.S. Centers for Disease Control and Prevention (CDC) estimates that 1 in 6 Americans get sick from eating contaminated food every year.

It can happen after food has been adulterated with physical, chemical and biological contaminants -- or any combination of those. Physical can include such products as rubber or glass; chemical can include such toxins as bleach and mercury; and biological can include many types of bacteria, viruses or parasites.

Food can be contaminated before it reaches a grocery store or home kitchen, and sometimes those who prepare food at a restaurant can pass along norovirus – the germ that is the leading cause of foodborne disease outbreaks worldwide.  

Examples of contamination in preparation

• If a food worker stays on the job while sick and does not wash his or her hands carefully, the food worker can spread germs by touching food.
• If a cook uses a cutting board or knife to cut raw chicken and then uses the same items somewhere else in the kitchen, other food could be contaminated by germs from the chicken.
• Contamination can occur in a refrigerator if liquids from meat or chicken get on items that will be eaten raw.

Mishandling at multiple points

Food can be mishandled in several ways along the food production chain. Once contamination occurs, further mishandling, such as undercooking the food or leaving it out on the counter at an unsafe temperature, can make a foodborne illness more likely. Many germs grow quickly in food held at room temperature; a tiny number can grow to a large number in just a few hours. Reheating or boiling food after it has been left at room temperature for a long time does not always make it safe because some germs produce toxins that are not destroyed by heat.

How to tell if you have food poisoning?

Food poisoning signs and symptoms may range from mild to severe and can differ significantly depending of the contaminant, according to the U.S. Centers for Disease Control and Prevention (CDC). The most common ways on how to know if you have food poisoning are:

• Upset stomach
• Stomach cramps
• Nausea
• Vomiting
• Diarrhea
• Fever

After you consume a contaminated food or drink -- especially if it is a chemical contaminant -- you may show symptoms of poisoning immediately. With some biological contaminants, it may take hours or days before you develop symptoms of food poisoning.

What causes food poisoning?

Food can be mishandled in several ways along the food production chain, all of which can result in food poisoning. Once contamination occurs, further mishandling, such as undercooking the food or leaving it out on the counter at an unsafe temperature, can make a foodborne illness more likely. Many germs grow quickly in food held at room temperature; a tiny number can grow to a large number in just a few hours. Reheating or boiling food after it has been left at room temperature for a long time does not always make it safe because some germs produce toxins that are not destroyed by heat.

• If a food worker stays on the job while sick and does not wash his or her hands carefully, the food worker can spread germs by touching food.
• If a cook uses a cutting board or knife to cut raw chicken and then uses the same items somewhere else in the kitchen, other food could be contaminated by germs from the chicken.
• Contamination can occur in a refrigerator if liquids from meat or chicken get on items that will be eaten raw.

For more information about:

Recalled Food

If you have food poisoning and want to check recently recalled foods, please visit these pages:

Recalls by the U.S. Food and Drug Administration

Recalls by the U.S. Department of Agriculture

Current Multistate Food Poisoning Outbreaks

Here is a list of current multistate foodborne illness outbreaks.

When two or more people get the same illness from the same contaminated food or drink, the event is called a foodborne or food poisoning outbreak. Reporting illnesses to your local health department helps them identify potential outbreaks of foodborne disease. Public health officials investigate outbreaks to control them, so more people do not get sick in the outbreak, and to learn how to prevent similar outbreaks from happening in the future.

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