Salmonellosis - Epidemiology

What is salmonellosis?

Salmonellosis is a disease caused by bacteria called Salmonella. It usually affects the intestine (bowels) and causes an illness that lasts several days to a week. If the Salmonella bacteria spread to the blood, a more serious illness develops.

Who gets salmonellosis?

Any person can get salmonellosis, but it is identified more often in infants and children. The elderly, infants, and those with weakened immune systems are more likely to experience severe illness.

How are Salmonella bacteria spread?

Salmonella must be swallowed to cause disease. The bacteria can be found in the feces (stool) of animals raised for food (such as poultry, pigs, cows), animals kept as pets (such as lizards, turtles, chicks, ducklings, dogs, and cats), and infected people. The feces can then contaminate raw meats, chicken, eggs, unpasteurized milk and cheese products and other foods, and people can get sick from eating these contaminated foods. Infected persons can spread the bacteria if they do not wash their hands well after going to the bathroom or after touching animals and then touching something (e.g., food, toys) that other people put in their mouth.

What are the symptoms of salmonellosis?

Symptoms of salmonellosis include diarrhea (non-bloody), abdominal cramps, headache, fever, and sometimes vomiting.

How soon after exposure do symptoms appear?

Symptoms typically occur from six hours to three days or more after exposure, but usually appear within 12-36 hours after exposure.

How is salmonellosis diagnosed?

Salmonellosis is diagnosed by laboratory testing of feces (stool).

What is the treatment for salmonellosis?

Most people with salmonellosis recover without treatment. Persons with diarrhea should drink plenty of fluids to prevent dehydration. Antibiotics and anti-diarrhea drugs are generally not recommended for mild to moderate illnesses. Persons with severe salmonellosis may require admission to a hospital for intravenous (I.V.) fluids and antibiotics.

How can salmonellosis be prevented?

Hand Hygiene

Wash hands carefully with soap and warm water before and after food preparation and after toileting or changing diapers.

Safe Food Handling

Refrigerate perishable foods promptly; minimize holding foods at room temperature.
Always treat raw poultry, beef, pork, and egg products as if they were contaminated.
Wrap fresh meats in plastic bags at the market to prevent fluids from dripping on other foods in the grocery cart.
Avoid eating raw or undercooked eggs (or foods made with raw eggs), poultry, and meats.
Avoid drinking raw (unpasteurized) milk.
Ensure that cooked foods reach the correct internal temperature, especially when using a microwave. See the CDC page on food safety methods for more information.
Wash raw fruits and vegetables prior to eating or chopping.
Disinfect food cutting boards, counters, and utensils after each use (1 tsp. liquid household bleach per gallon of water is effective - prepare the bleach solution fresh daily). Do not rinse. Let air dry.

Contact with animals

Avoid chicks, ducklings, turtles, and other reptiles as pets for small children.
Do not allow children to handle pet foods or pet treats.
Supervise children at farms, petting zoos, and other environments where they may have contact with livestock (e.g., calves, sheep, goats, etc.).
Assure that children wash their hands after touching animals.

How long can an infected person carry the Salmonella bacteria?

Most people carry the bacteria for several days to several weeks after illness. A small percentage of infected persons carry the bacteria a year or longer.

Should an infected person be excluded from work or school?

People who have diarrhea should not work as food handlers, or provide care for children or patients. Children who have diarrhea should not go to child care or school. Most infected people may return to work or school when diarrhea stops, provided that they are careful to wash their hands after using the toilet. In some situations, people who are infected with Salmonella, even if they do not have any symptoms, may need to be excluded from high-risk environments until they have no Salmonella in their stool. The local health department should be involved in discussions regarding when persons infected with Salmonella who are in high risk settings may safely return to those settings.

How can I get more information about salmonellosis?

If you have concerns about salmonellosis, contact your healthcare provider.
Call your local health department. A directory of local health departments is located at the VDH Local Health Districts page.
Visit the Centers for Disease Control and Prevention website at the CDC page on Salmonella.