What is food poisoning?

Food poisoning (also called foodborne illness) causes vomiting, diarrhea, and abdominal pains. Symptoms usually go away within a few days, but in severe cases, food poisoning can cause significant morbidity (many health consequences). Food poisoning occurs when a person consumes food or beverages contaminated by:

  • Bacteria.
  • Viruses.
  • Parasites.
  • Toxins, chemicals and molds.

There are more than 250 types of food poisoning. Some of the most common germs and parasites that cause food poisoning are:

  • E. coli: Usually found in undercooked meat and raw vegetables, E. coli can cause serious health problems, especially in young children.
  • Listeria: Bacteria in soft cheeses, deli meats, and raw sprouts can cause an infection called listeriosis, which is especially dangerous for pregnant women.
  • Norovirus: People can get norovirus by eating undercooked shellfish or consuming food that a sick person prepared.
  • Salmonella: Raw eggs and undercooked poultry are common sources of salmonella poisoning. Salmonella is responsible for the highest number of hospitalizations and deaths from food poisoning.
  • Staphylococcus aureus (staph): A staph infection occurs when people transfer the staph bacteria from their hands to food.
  • Clostridium perfringens: Raw meat or poultry, pre-cooked foods are common sources of clostridium. It can cause gastrointestinal (GI) symptoms (nausea, vomiting, abdominal pains, and diarrhea) within 6-24 hours. It generally lasts a day or two but can last weeks in some people.
  • Campylobacter: This common bacterial infection producing severe GI upset can linger for weeks. Usually, culprits are found in poorly processed meats or contaminated vegetables, milk, or water sources. The condition is generally self-limited and is rarely fatal.
  • Trichinella spiralis: This worm is found in raw or undercooked meats, particularly pork products.

Other common causes of food poisoning include cryptosporidium and streptococcus.

How common is food poisoning?

Food poisoning is very common. Most cases aren’t severe enough to require hospitalization. According to the CDC, about 48 million people experience some type of food poisoning each year in the United States. Around 3,000 people die from foodborne illness every year.

Who is affected by food poisoning?

Everyone is at risk of getting food poisoning, but certain groups of people are more likely to get sick after eating contaminated food. People who have a higher risk of foodborne illness are:

  • Pregnant women.
  • Older adults (over age 65).
  • Young children (under age 5).
  • People who have a weakened immune system due to cancer, HIV, or other illness.

What are the symptoms of food poisoning?

Food poisoning symptoms range from mild to severe and vary depending on the type of contamination. Symptoms may appear 1 to 6 hours after eating contaminated food, or they may take days or weeks to develop. A well-known symptom of food poisoning is diarrhea. Other common symptoms of foodborne illness include:

How do people get food poisoning?

People get foodborne illness by eating or drinking contaminated food, water, and other beverages. Food can become contaminated at any time during storage, preparation and cooking. Contamination occurs when food is not:

  • Washed thoroughly.
  • Handled in a sanitary way.
  • Cooked to a safe internal temperature.
  • Refrigerated or frozen promptly.

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