Symptoms of Salmonella

Salmonella is a bacteria that can cause salmonellosis (non-typhoidal Salmonella enteritis), a common foodborne infection that causes watery diarrhea, fever, and abdominal cramps. The symptoms usually last about four to seven days and don't typically require a trip to the healthcare provider, unless it affects an infant or if complications develop. Dehydration is the most common complication, and less frequent complications include blood infection and invasive salmonella infection.

Salmonella symptoms
© Verywell, 2018

Frequent Symptoms

Symptoms of a gastrointestinal Salmonella infection can begin within six hours and up to four days after you are exposed. The typical incubation period is 12 to 36 hours. You will have symptoms of gastroenteritis (stomach flu).

The typical symptoms usually include:

  • Watery diarrhea: This is the chief symptom and it usually comes on suddenly. At times, diarrhea can also be bloody or have mucus.
  • Fever: This almost always occurs with this infection, and you may also have chills.
  • Abdominal pain and abdominal cramps: You are likely to have this symptom intermittently.

Less frequent, but fairly common symptoms include nausea, vomiting, loss of appetite, and headache. Watery diarrhea can lead to further symptoms of dehydration if you don't drink enough water to keep up with your fluid loss.

The symptoms may be more severe in young children, older people, or people who have weakened immune systems.

These symptoms usually last about four to seven days and often go away without treatment. However, diarrhea can continue for as long as 10 days. After recovery, your bowel habit may be changed and might not return to normal for several months.

Most types of Salmonella bacteria cause gastrointestinal disease, but Salmonella typhi is a type that causes typhoid fever, a severe flu-like illness that's endemic to certain parts of South Asia, Africa, the Caribbean, and Central and South America.


The most frequent complication of salmonellosis is dehydration, and anyone with severe diarrhea or vomiting is at risk, especially if they are not drinking enough water or an electrolyte solution (Pedialyte or sports drinks like Gatorade) to keep up with the fluid loss.

Dehydration is more likely to occur in babies, young children, older adults, and pregnant women.

Common symptoms of dehydration:

  • Decreased urine production
  • Dry mouth
  • Fewer tears
  • Sunken eyes

You may also feel tired, dizzy, weak, confused, and have a headache. Severe dehydration can require emergency treatment and hospitalization.

Invasive Salmonella Infection

The bacteria can enter the bloodstream, where they can then spread to various tissues throughout the body.

Invasive salmonella infection affects about 8% of people who have confirmed salmonellosis. While this number sounds alarming, many people do not see their healthcare provider for milder cases and so their cases are never confirmed (and therefore aren't counted in this percentage).

Invasive infections can cause:

  • Meningitis if it infects the brain or spinal cord
  • Osteomyelitis if it infects bones
  • Septic arthritis if it infects a joint

These infections are serious and can be life-threatening.

Invasive infection is more common among high-risk groups of young children, the elderly, and people who are immunocompromised.

Antibiotic resistance has been seen for Salmonella species, and this can complicate treatment for invasive infections. Your healthcare provider may need to use powerful antibiotics that can cost more and might have more toxic side effects.

Reactive Arthritis

After recovering from salmonellosis, you have a greater risk of developing reactive arthritis. The infection triggers inflammation that can result in painful joints (especially the knees, ankles, and feet), irritated eyes, or pain when urinating.

This is not common and it tends to affect people age 20 to 40. It usually will resolve in a year.

When to See a Healthcare Provider

You do not need to see your healthcare provider if you have a typical case of salmonellosis without severe symptoms that improve after a few days.

You should see your healthcare provider if you or your child has symptoms of dehydration. Other concerning symptoms that should be checked by your healthcare provider or your child's pediatrician include a high fever, severe or worsening abdominal pain, or bloody stools.

High-Risk Groups

People in the high-risk groups, which include infants, children under age 5, and the elderly may need medical attention for evaluation and treatment of salmonellosis. Some pediatricians recommend that infants who have symptoms of this infection should always see the healthcare provider.

Other groups at risk of a severe infection or invasive infection include:

  • Those with a compromised immune system (HIV infection, cancer treatment)
  • People who have sickle cell disease
  • Anyone who has had a splenectomy
  • People who are taking medications that suppress the stomach acid

Signs of an Emergency

You should get emergency treatment or call 911 if you or your child has these symptoms, which can indicate life-threatening dehydration or the development of invasive salmonella infection:

  • Difficulty breathing
  • Passing out (fainting)
  • Feel or exhibit confusion
  • Feel very drowsy, have difficulty being woken up
  • Heart rate is rapid
  • Stiff neck or seizure (signs of meningitis)

Frequently Asked Questions

  • What foods are most often associated with Salmonella bacteria?

    A wide variety of foods have been linked to gastrointestinal Salmonella infections. According to the Centers for Disease Control and Prevention, as many as a million cases of food-borne Salmonella infection occur each year due to foods such as cucumbers, bean sprouts, poultry, pork, and eggs, and more. Even processed foods like peanut butter and chicken nuggets have been implicated.

  • What color is your poop when you have salmonella poisoning?

    It may be greenish in color. This is because the infection causes stool to pass through the digestive system more rapidly than is normal, so it contains more bile (a greenish-yellow digestive fluid) than stool that moves through the gastrointestinal tract at a slower rate.

  • How do the symptoms of salmonella poisoning compare to those of E. coli infection?

    Because both are food-borne illnesses, the symptoms of each are strikingly similar: Both Salmonella and Escherichia coli (E. coli) bacteria cause watery diarrhea (that sometimes is bloody), stomach cramps, vomiting, and in some cases, a mild fever. Salmonella infections are considerably more common than E. coli infections.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. CDC. Salmonella.

  2. Centers for Disease Control and Prevention. Salmonella. Symptoms

  3. U.S. National Library of Medicine. MedlinePlus. Salmonella enterocolitis

  4. Centers for Disease Control and Prevention. Salmonella. Information for Healthcare Professionals and Laboratories

  5. Centers for Disease Control and Prevention. Salmonella. Questions and answers.

  6. Centers for Disease Control and Prevention. Salmonella and Food.

  7. Tan CK, Chao CM, Lai CC. Green fecesQJM. 2013 Jan;106(3):287. doi:10.1093/qjmed/hcr271

  8. MedlinePlus. E. Coli Infections.

Additional Reading

By Vincent Iannelli, MD
 Vincent Iannelli, MD, is a board-certified pediatrician and fellow of the American Academy of Pediatrics. Dr. Iannelli has cared for children for more than 20 years.