Questions and Answers
What are Salmonella?
Salmonella are bacteria that make people sick. They were first discovered by an American scientist named Dr. Daniel E. Salmon in 1885.
What illness do people get from Salmonella infection?
Most types of Salmonella cause an illness called salmonellosis, which is the focus of this website. Some other types of Salmonella cause typhoid fever or paratyphoid fever.
What are the symptoms of infection?
Most people with Salmonella infection have diarrhea, fever, and stomach cramps.
Symptoms usually begin six hours to six days after infection and last four to seven days. However, some people do not develop symptoms for several weeks after infection and others experience symptoms for several weeks.
Salmonella strains sometimes cause infection in urine, blood, bones, joints, or the nervous system (spinal fluid and brain), and can cause severe disease.
Scientists classify Salmonella into serotypes (types) by identifying structures on the bacteria’s surfaces. Although more than 2,500 serotypes have been described, fewer than 100 are known to cause human infections.
How is Salmonella infection diagnosed?
Salmonella infection is diagnosed when a laboratory test detects Salmonella bacteria in a person’s stool (poop), body tissue, or fluids.
How is infection treated?
Most people recover from Salmonella infection within four to seven days without antibiotics. People who are sick with a Salmonella infection should drink extra fluids as long as diarrhea lasts.
Antibiotic treatment is recommended for:
- People with severe illness
- People with a weakened immune system, such as from HIV infection or chemotherapy treatment
- Adults older than 50 who have medical problems, such as heart disease
- Infants (children younger than 12 months).
- Adults age 65 or older
Can infection cause long-term health problems?
Most people with diarrhea caused by Salmonella recover completely, although some people’s bowel habits (frequency and consistency of poop) may not return to normal for a few months.
Some people with Salmonella infection develop pain in their joints, called reactive arthritis, after the infection has ended. Reactive arthritis can last for months or years and can be difficult to treat. Some people with reactive arthritis develop irritation of the eyes and pain when urinating.
How do people get infected?
Salmonella live in the intestines of people and animals. People can get Salmonella infection from a variety of sources, including
- Eating contaminated food or drinking contaminated water
- Touching infected animals, their feces, or their environment
Who is more likely to get an infection and severe illness?
- Children under 5 years old are the most likely to get a Salmonella infection.
- Infants (children younger than 12 months) who are not breast fed are more likely to get a Salmonella infection.
- Infants, adults aged 65 and older, and people with a weakened immune system are the most likely to have severe infections.
- People taking certain medicines (for example, stomach acid reducers) are at increased risk of infection.
What should I know about antibiotic resistance and Salmonella?
Resistance to essential antibiotics is increasing in Salmonella, which can limit treatment options for people with severe infections. One way to slow down the development of antibiotic resistance is by appropriate use of antibiotics.
What can be done to prevent antibiotic resistance and resistant bacteria?
Appropriate use of antibiotics in people and animals (use only when needed and exactly as prescribed) can help prevent antibiotic resistance and the spread of resistant bacteria.
How common is Salmonella infection?
CDC estimates Salmonella cause about 1.35 million illnesses, 26,500 hospitalizations, and 420 deaths in the United States every year.
- CDC. Antibiotic Resistance Threats in the United States, 2019. Atlanta, GA: U.S. Department of Health and Human Services, CDC; 2019.
- Scallan E, Hoekstra RM, Angulo FJ, Tauxe RV, Widdowson MA, Roy SL, Jones JL, Griffin PM. Foodborne illness acquired in the United States–major pathogens pdf icon[PDF – 9 pages]. Emerging Infectious Diseases. 2011;17(1):7-15.
- CDC. Foodborne Diseases Active Surveillance Network (FoodNet): FoodNet Surveillance Report for 2012 (Final Report) pdf icon[PDF 9 – pages]. Atlanta, Georgia: U.S. Department of Health and Human Services, CDC. 2014.
- CDC. Suspecting Foodborne Illnesses in Special Populations: Quick Facts for Providersexternal icon. Atlanta, Georgia: U.S. Department of Health and Human Services, CDC. 2012.
- Carter JD, Hudson AP. Reactive arthritis: clinical aspects and medical managementexternal icon. Rheum Dis Clin North Am. 2009 Feb; 35(1): 21-44.