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This fact sheet answers frequently asked questions about shigella.

Shigella is a bacteria that causes an infectious disease of the intestines called shigellosis.

The basics

How do people catch shigella?

You get shigella by swallowing the bacteria. You only need a small number of bacteria to cause illness. The bacteria often spread when people do not wash their hands with soap and water after using the toilet or changing a diaper. People who get bacteria on their hands can infect themselves by eating, smoking, or touching their mouths. People who have sex with people who have the disease are at risk of catching it if there is contact between the mouth and genital area. The germs can also spread through food or beverages prepared by a person with shigella infection. In rare cases, shigella germs can also spread through swimming pools or contaminated lakes and ponds.


What are the symptoms of shigella infection?

The most common symptoms are diarrhea, fever, stomach cramps, and straining to go to the bathroom. The stool may be watery or contain blood, mucus, or pus. Symptoms usually begin 1 to 2 days after swallowing the bacteria. The symptoms generally last for five to seven days.

Do all infected people have symptoms?

No. Some only have mild symptoms. Sometimes people infected with shigella have no symptoms at all, but can still pass the bacteria.

How do you know if you have shigella infection?

Your healthcare provider can send a stool sample to a laboratory. The laboratory will test the sample for shigella bacteria. 


How can you prevent shigella?

People with shigella infection should not prepare food or drinks for others. You can prevent the spread of shigella with frequent hand washing with soap and water.

Hand washing saves lives!

Wash your hands:

  • Before, during, and after preparing food
  • Before eating food
  • After using the toilet
  • After changing diapers or cleaning up a child who has used the toilet

Healthy Swimming Tips:

  • Do not swallow water or get water in your mouth while swimming
  • Take a shower before swimming
  • Do not swim when you have diarrhea
  • Change diapers in changing rooms, not poolside, or on the beach. Wash hands after changing diapers


How is the illness treated?

People with mild infections usually recover without antibiotic treatment. However they may need extra fluids to prevent dehydration. Antibiotics can treat shigella infection in people who cannot fight off the illness on their own. Avoid medicines that control diarrhea as they can make the illness worse. If food workers and health care workers get shigella, they will need to be cleared to return to work from their local health department.

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