Last Reviewed: May 2023

What is shigellosis?

Shigellosis is an intestinal (bowel) infection caused by a group of bacteria called Shigella. It causes diarrhea (loose stool/poop) in humans and spreads easily from person to person. Shigellosis is a fairly common disease; there are an estimated 450,000 infections in the United States each year.

Who gets shigellosis?

Anyone can get shigellosis, but it is recognized more often in young children. Those who may be at greater risk include children in daycare centers, travelers to certain foreign countries, people who have weakened immune systems, and people exposed to human feces (poop) through sexual contact. Large outbreaks of shigellosis have occurred in communities which often begin in childcare settings and spread throughout households and the community during social gatherings. Outbreaks have also occurred among gay or bisexual men and other men who have sex with men.

How is shigellosis spread?

Shigella is found in the intestinal tract (bowels) of infected people and is shed in their feces (poop). People get shigellosis by putting anything in their mouth that has touched infected feces or by eating or drinking food or water contaminated with the bacteria. It can also be spread sexually by oral-anal contact. Even accidentally swallowing a tiny (too small to see) amount of contaminated feces can spread infection to a healthy person. Shigella bacteria are present in the feces of infected persons while they are sick and for up to a week or two after they no longer feel ill.

What are the symptoms of shigellosis and when do they appear?

People with shigellosis usually experience mild or severe diarrhea (loose stool/poop), sometimes with fever, stomach pain, and traces of blood or mucous in the stool. These symptoms usually last 5-7 days. Some infected people may not show any symptoms. The symptoms may appear one to seven days after exposure, but usually within one to two days.

How is shigellosis diagnosed?

Since diarrhea can be caused by many different infections, laboratory tests that identify Shigella bacteria in the stool (poop) of an ill person are needed to diagnose shigellosis.

How is shigellosis treated?

Most people with shigellosis will recover on their own by consuming fluids and resting. Some may require intravenous fluids to prevent dehydration (loss of water in the body causing weakness or dizziness). Antibiotics are occasionally used to treat severe cases to shorten the duration of symptoms.

Should infected people be isolated or excluded from work or school?

Most infected people may return to work or school when their diarrhea (loose stool/poop) has stopped, provided that they carefully wash their hands with soap and water after toilet visits. Food workers, health care personnel, and children in daycare must obtain approval from the local or state health department before returning to work or daycare.

What can be done to prevent the spread of shigellosis?

Since Shigella is passed in feces (poop), careful handwashing with soap and water after using the toilet or handling soiled diapers and proper disposal of sewage is the most important way to prevent shigellosis. People with shigellosis should avoid sexual contact until at least two weeks after diarrhea resolves.