Shigella infection (shigellosis) is an intestinal condition caused by a family of bacteria known as shigella. The major sign of shigella infection is diarrhea, which is usually bloody.
Shigella can be transmitted through direct contact with the bacteria found in the stool. For example, this can occur in a child care setting when staff members don’t wash their hands very well after changing diapers or helping toddlers with toilet training. Shigella bacteria also can be transmitted in contaminated food or by drinking or swimming in contaminated water.
Children below age 5 are most likely to suffer shigella infection, but it can occur happen at any age. A mild case often clears up on its own within a week. When treatment is required, doctors generally prescribe antibiotics.
Signs and symptoms of shigella infection often begin a day or two after infected with shigella, but may take up to a week to develop. Signs and symptoms may include:
Abdominal pain or cramps
Diarrhea (often containing blood or mucus)
Although some people experience no symptoms after they’ve been infected with shigella, their feces may still be contagious up to a few weeks.
When to see a doctor
See your doctor or seek urgent care if you or your child experience bloody diarrhea or diarrhea serious enough to cause weight loss and dehydration. Also, contact your doctor if you or your child suffers diarrhea and a fever of 101 F (38 C) or higher.
Infection happens when you accidentally swallow shigella bacteria. This occurs when you:
Touch your mouth: If you don’t wash your hands very well after changing the diaper of a baby who has shigella infection, you may become infected yourself. Direct person-to-person contact is the most common way the infection is spread.
Eat contaminated food: Infected people who come in contact with food can transmit the bacteria to those who eat the food. Food can also become contaminated if it grows in a field that has sewage.
Swallow contaminated water: Water may become contaminated from either sewage or from an infected person with shigella swimming in it.
Age: Children below age 5 are most likely to be infected shigella infection, but it can happen at any age.
Living arrangements and activities: Close contact with other infected people spreads the bacteria from person to person. Shigella outbreaks are mostly common in child care centers, nursing homes, community wading pools, jails and military barracks.
Time spent in areas that lack sanitation: People who reside or travel in developing countries are more liable to contract shigella infection.
Men who have sex with men: Men who have sex with men are at greater risk due to direct or indirect oral-anal contact.
Shigella infection often clears up without complications, although it may take between weeks to months before your bowel habit properly return to normal.
Complications may include:
Dehydration: Persistent diarrhea can result to dehydration. Symptoms may include dizziness, lightheadedness, and lack of tears in children, sunken eyes and dry diapers. Severe dehydration can cause shock and death.
Seizures: Some children who experience high fevers with a shigella infection suffer seizures. It’s not clear whether the convulsions are a result of the fever or the shigella infection itself. If your child has a seizure, see your doctor immediately.
Rectal prolapsed: In this condition, straining during bowel movements may lead to mucous membrane or lining of the rectum to move out through the anus.
Hemolytic uremic syndrome: This unusual complication of shigella, more commonly results from bacteria called E. coli, can cause a low platelet count (thrombocytopenia), low red blood cell count (hemolytic anemia), and acute kidney failure.
Toxic megacolon: This rare complication happens when your colon becomes paralyzed, stopping you from having a bowel movement or passing gas. Signs and symptoms may include abdominal pain and fever, swelling, and weakness. If you don’t take treatment for toxic megacolon, your colon may break open (rupture), causing peritonitis, and dangerous infection requiring emergency surgery.
Reactive arthritis: Reactive arthritis occurs in response to an infection. Signs and symptoms may include joint pain and inflammation, often in the ankles, feet, knees, and hips; redness, itching and discharge in one or both eyes (conjunctivitis); and painful urination (urethritis).
Although studies continue their work to develop a shigella vaccine, nothing is available yet. To stop the spread of shigella:
Wash hands thoroughly and frequently
Dispose of soiled diapers properly
Disinfect diaper-changing areas after use
Keep children with diarrhea home from child care, play groups or school
Supervise small children when they wash their hands
Don’t make food for others if you have diarrhea
Avoid swallowing water from lakes, ponds, or untreated pools
Avoid sexual engagement with anyone who has diarrhea or who recently suffered from diarrhea