Food poisoning is more common than you think. According to the U.S. Centers for Disease Control and Prevention (CDC), about one in six people in the United States get food poisoning each year. That’s about 48 million people. We usually only hear about food poisoning when there’s a food recall or when a restaurant is linked to an outbreak. In cases like this it may become big news, as it did recently after the CDC posted an alert about recalls of some deli meats due to contamination with listeria.
Most cases of food poisoning come from improperly prepared meals at home or at outdoor gatherings where food like deviled eggs, tuna salad, or other dishes sit out in the sun for too long. In this Q&A, Bernard Camins, MD, Professor of Medicine (Infectious Diseases) at the Icahn School of Medicine at Mount Sinai and the Medical Director for Infection Prevention for the Mount Sinai Health System, discusses food poisoning and when you may need to go seek medical care.
What are the symptoms of food poisoning?
Symptoms of food poisoning can include nausea, vomiting, diarrhea, and sometimes fever. You may not have these symptoms right away. Depending on the type of food poisoning you have, it can take 24 to 48 hours, or even a little longer, until you develop symptoms.
When should I go to the doctor?
Most people recover from food poisoning on their own. Once your body has eliminated the toxin or the offending agent, you may recover on your own. If you experience symptoms for more than three days, if you become dehydrated and cannot keep liquids down, or if you have a fever for more than 24 hours, it’s time to see a physician.
How do I prevent food poisoning?
The majority of food poisoning happens at home. There are a few basic rules to prevent it:
- Washing is very important. Wash your hands with soap and warm water for at least 20 seconds before, during, and after preparing food, and before eating. Always wash your hands after handling eggs, flour, or uncooked meat. Don’t forget to rinse your fruits and vegetables under running water. Also, wash your knives and other utensils, cutting boards, and countertops with hot soapy water after preparing each type of food, especially raw meat or unwashed vegetables.
- Keep uncooked meat, poultry, fish, and eggs separate from everything else. They harbor bacteria that can cause infections. That means keeping them separate all the way from the supermarket to your refrigerator at home. Meat, poultry, and fish, especially might leak liquids that could spread germs. If possible, use two cutting boards—one for raw meat, seafood, and poultry and another one for produce, bread, and other foods you serve raw.
- Cook meat, poultry, and fish to the recommended temperature. You can use a meat thermometer to check. If you use the microwave, follow the directions carefully; for instance, letting food sit after you’ve microwaved it can help it cook more thoroughly.
- Refrigerate your food carefully. Don’t let perishables sit out on the table or counter for more than two hours—or, if it’s over 90 degrees Fahrenheit, not more than one hour. Thaw food in the refrigerator, in cold water, or in the microwave, not on the counter. Thawing on the counter can allow bacteria to grow more quickly.
- Keep on top of food recalls. You can check the website from the CDC to see what foods are being recalled due to contamination. If it turns out you have a food that has been recalled, throw that food out right away. Then clean the refrigerator shelves and drawers thoroughly, because germs in the recalled food could easily spread throughout your fridge.
What are the most common causes of food poisoning?
The most common causes of food poisoning are:
- Norovirus: This highly contagious virus causes vomiting and diarrhea. This has caused numerous outbreaks on cruise ships.
- Salmonella (non–typhoid): Salmonella is actually the name of the bacteria that causes infection from contaminated food. The salmonella infection leads to diarrhea, fever, and stomach cramps.
- Clostridium perfringens: Caused by meat, poultry, and gravy kept at an unsafe temperature, clostridium perfringens results in diarrhea and stomach cramps.
- Campylobacter: Usually stemming from eating raw or uncooked poultry or drinking untreated water, campylobacter gives you diarrhea.
- Staphylococcus aureus: This bacterium primarily causes skin and soft tissue infection. Some people can carry it on their hands. When they prepare or serve food without washing hands, this bacteria can produce a toxin that causes nausea, vomiting, stomach cramps, and diarrhea.
It is worth noting that listeriosis, or listeria infection, is rare compared with these other illnesses. Listeriosis can become serious and can be fatal for people at higher risk for severe disease, such as the elderly, pregnant persons, and people with weakened immune systems. The CDC says that the good news is that the listeria bacteria are easily killed by heating food to a high enough temperatures, and following the other basic food-safety steps.