Salmonella (Salmonellosis)

Medically Reviewed by Carol DerSarkissian, MD on March 15, 2024
5 min read

Salmonella is the type of bacteria that’s the most frequently reported cause of food-related illness in the United States. You can’t see, smell, or taste it.

Illness from these bacteria is officially called salmonellosis. It can cause an upset stomach, diarrhea, fever, and pain and cramping in your belly. Most people get better on their own at home within 4 to 7 days.

Salmonella infections are very common. When people mention food poisoning, they’re usually talking about salmonella. Tens of millions of cases are reported around the world every year.

In severe cases, you need to go to the hospital. Rarely, it can be life-threatening.

Infections are more common in the summer than the winter. This is because salmonella grows quickly in higher temperatures, when food isn’t refrigerated.

People and animals can carry salmonella in their intestines and their feces. The bacteria often spread through contaminated foods. Common food sources of salmonella infection include:

  • Raw and undercooked meat, including chicken, turkey, duck, beef, veal, and pork
  • Raw fruits or vegetables
  • Unpasteurized milk and other dairy products, including soft cheese, ice cream, and yogurt
  • Raw or undercooked eggs
  • Processed foods like chicken nuggets and nut butters

You can also get salmonella directly through:

  • Poor handwashing. You might pass along the bacteria by not washing your hands well after using the bathroom or changing a diaper.
  • Pets. Animals like dogs, cats, birds, and reptiles can carry the bacteria.

 

Children, especially those under 5, are more likely than adults to get sick from salmonella. Older adults and people with weak immune systems are also more likely to be infected. Other risk factors include:

  • International travel. Salmonella is more common in places with poor sanitation.
  • Taking certain drugs.Cancer drugs or steroids can weaken your immune system. Antacids lower how much acid is in your stomach, which makes it easier for salmonella to survive there. Antibiotics can kill “good” bacteria in your body and make an infection harder to fight.
  • Inflammatory bowel disease. This can damage the lining of your intestines, making it easier for salmonella to take hold.

 

Most of the signs and symptoms of a salmonella infection are stomach-related. They include:

Symptoms tend to start 8 to 72 hours after infection. Most symptoms usually don’t last more than a week, but it can take several months for your bowel movements to get back to normal.

When should I call a doctor?

See your doctor if you’re still having general symptoms more than a week after first getting the infection.

A young child, an older adult, or someone who has a weakened immune system should see a doctor if they have any of these symptoms for more than a couple of days:

  • Bloody poop
  • Ongoing high fever
  • Dehydration, when they’ve lost too much fluid. Signs include peeing only in small amounts, a dry mouth, and sunken eyes.

 

You can become dehydrated if you don’t get enough fluids to replace what you lose because of diarrhea.

A few people who get a salmonella infection also get pain in their joints. You might hear a doctor call it reactive arthritis or Reiter’s syndrome. It can last several months or longer. This condition can also cause pain while peeing and itchy, stinging, or sore eyes.

If the salmonella infection gets into your blood, it can infect other parts of your body, including:

  • The tissues around your brain and spinal cord
  • The lining of your heart or heart valves
  • Your bones or bone marrow
  • The lining of your blood vessels

 

Your doctor may have you take blood tests, or they might ask for a sample of your poop.

Sometimes, they may want to do testing to figure out the exact kind of bacteria you have. This can help health officials trace the source if there’s an outbreak in your area.

For healthy adults: If you have diarrhea, drink a lot of water and other fluids. Your doctor might suggest that you drink a rehydration liquid like Pedialyte or take a medication like loperamide (Imodium) if your diarrhea is severe.

If your doctor confirms that you have a salmonella infection, they might prescribe antibiotics. Take them exactly as directed, and be sure to finish the prescription.

For children: If your child has a healthy immune system, the doctor might just let the infection run its course. If they have a high fever, you may want to give acetaminophen. As with adults, they should drink lots of water.

In special cases: Infants, the elderly, and people who have weakened immune systems may need antibiotics.

Salmonella can hide in a variety of foods, but you can do a lot of things to help ensure the bacteria stay away:

  • Don’t eat raw or barely cooked eggs or meat.
  • Don’t eat or drink anything with unpasteurized milk or juice.
  • Don’t wash raw poultry, meat, or eggs before cooking.
  • Wash raw fruits and vegetables well, and peel them if possible.
  • Don’t prepare food for other people if you’re vomiting or have diarrhea.
  • Refrigerate food properly, both before cooking it and after serving it.
  • Wash your hands well with soap and warm water before and after handling food.
  • Keep kitchen surfaces clean before preparing food on them.
  • Don’t mix cooked food with raw food or use the same utensils to prepare them. For example, don’t use the same knife to cut raw chicken and then to slice mushrooms, and use different plates or cutting boards to slice them on.
  • Cook meat to its correct minimum temperature. Use a food thermometer to be sure.
  • Wash your hands with soap and water after touching animals, their toys, and their bedding.