Photomicrograph revealed stool exudates in a patient with shigel

What is shigellosis?

Shigellosis is an infectious disease caused by a group of bacteria called Shigella.  There are 4 types of Shigella:

  • Shigella sonnei (the most common species in the United States)
  • Shigella flexneri
  • Shigella boydii
  • Shigella dysenteriae

S. dysenteriae and S. boydii are rare in the United States, but they are still prominent in the developing world.

Who is at risk for shigellosis?

  • Young children
  • Gay, bisexual, and other men who have sex with men
  • HIV-infected persons
  • Traditionally observant Jewish communities
  • Travelers

What are the symptoms of shigellosis?

Symptoms begin 1-2 days after exposure and usually last 5-7 days.  Most people recover completely, although bowel movements may take months to become regular.  Once a person has shigellosis, they are not likely to get the same type for years.  However, they are still susceptible to other types. Symptoms include:

  • Diarrhea (occassionally bloody)
  • Fever
  • Abdominal pain
  • Tenesmus (painful sensations of needing to pass stools even when bowls are empty)

What complications are associated with shigellosis?

  • Post-infectious arthritis: About 2% of patients with shigellosis will get develop painful joints, irritated eyes, and painful urination. Normally, only patients pre-disposed to arthritis will get this.
  • Blood stream infections: This is very rare and usually only happens in patients with weakened immune systems.
  • Seizures: Seizures happen occasionally, usually in young children.  It is not known why they occur, but they normally go away on their own.
  • Hemolytic-uremic syndrome (HUS): HUS is only associated with Shigella, and occurs when bacteria enters through the digestive system.  The bacteria produces a toxin that kills red blood cells. Patients with HUS normally have bloody diarrhea.

How is shigellosis diagnosed?

Many different types of bacteria can cause diarrhea, so laboratory tests may be used to determine shigellosis. Determining what type of disease is causing diarrhea can help guide proper treatment.

How is shigellosis treated?

Diarrhea associated with shigellosis often goes away without treatment after 5-7 days.  People with mild shigellosis normally require rest and fluids, although over-the-counter medications such as Bismuth subsalicylate can help.  Antibiotics can help severe cases, although Shigella is oftentimes resistant to antibiotics.  If your doctor prescribes you antibiotics, and you are not better within a few days, contact your healthcare provider to do additional tests to determine which antibiotic is right for you.

How can I prevent shigellosis?

To prevent getting shigellosis:

  • Wash your hands before eating and after changing a diaper/cleaning somebody that has recently defecated.
  • If you are caring for a baby with shigellosis, dispose of their soiled diapers in a lidded, lined garbage can.  Wash your hands and the baby’s hands immediately after changing the diaper.  Clean up leaks or spills immediately.
  • Avoid swallowing water from untreated water.
  • Avoid sexual activity with somebody who has shigellosis, or diarrhea in general.

To prevent spreading shigellosis:

  • Wash your hands after using the toilet.
  • Do not prepare food for others while you are sick.
  • Avoid swimming.
  • Do not have sex until you are completely recovered.
  • Do not go to work if you work in healthcare, food service, or child care facilities

To prevent your child from spreading shigellosis:

  • Supervise handwashing for children, and make sure they wash their hands after using the toilet
  • Do not send your child to daycare until their diarrhea has stopped completely
  • Avoid taking your child swimming

For more information on shigellosis, click here.