Shigella infection (shigellosis) is an intestinal infection caused by a family of bacteria known as shigella. The main sign of shigella infection is diarrhea, which often is bloody.
Shigella is very contagious. People get infected with shigella when they come in contact with and swallow small amounts of bacteria from the stool of a person who is infected with shigella. For example, this can happen in a child care setting when staff members don't wash their hands well enough after changing diapers or helping toddlers with toilet training. Shigella bacteria can also be passed in infected food or by drinking or swimming in unsafe water.
Children under age 5 are most likely to get shigella infection, but it can occur at any age. A mild case usually clears up on its own within a week. When treatment is needed, doctors generally prescribe antibiotics.
Signs and symptoms of shigella infection usually begin a day or two after contact with shigella. But it may take up to a week to develop. Signs and symptoms may include:
Symptoms generally last for about five to seven days. In some cases, symptoms may last longer. Some people have no symptoms after they've been infected with shigella. However, their feces may still be contagious up to a few weeks.
Contact your doctor or seek urgent care if you or your child has bloody diarrhea or diarrhea severe enough to cause weight loss and dehydration. Also, contact your doctor if you or your child has diarrhea and a fever of 101 F (38 C) or higher.
Infection occurs when you accidentally swallow shigella bacteria. This can happen when you:
Shigella infection usually clears up without complications. But it may take weeks or months before your bowel habits return to normal.
Complications may include:
Although researchers continue to work to develop a shigella vaccine, nothing is available yet. To prevent the spread of shigella:
Diarrhea and bloody diarrhea can result from a number of diseases. Confirming shigella infection involves taking a sample of your stool to be tested in a lab for the presence of shigella bacteria or their toxins.
Shigella infection usually runs its course in five to seven days. Replacing lost fluids from diarrhea may be all the treatment you need, particularly if your general health is good and your shigella infection is mild.
Talk to your doctor before taking an over-the-counter (OTC) drug intended to treat diarrhea. Diarrhea can be caused by a number of conditions, and OTC drugs may make some conditions worse.
If a lab test has confirmed that you have shigella infection, an OTC drug containing bismuth subsalicylate (Pepto-Bismol, Kaopectate) may help decrease the frequency of your stools and shorten the length of your illness. However, it isn't recommended for children, pregnant women or people who are allergic to aspirin.
Avoid taking OTC anti-motility drugs, such as loperamide (Imodium) and drugs containing the combination of diphenoxylate and atropine (Lomotil). These aren't recommended for shigella infection because they can decrease your body's ability to clear the bacteria and make your condition worse.
For severe shigella infection, antibiotics may shorten the length of the illness. However, some shigella bacteria have become drug resistant. So your doctor may not recommend antibiotics unless your shigella infection is severe.
Antibiotics may also be necessary for infants, older adults and people who have HIV infection, as well as in situations where there's a high risk of spreading the disease.
For generally healthy adults, drinking water may be enough to counteract the dehydrating effects of diarrhea.
Children may benefit from an oral rehydration solution, such as Pedialyte, available in drugstores. Many pharmacies carry their own brands.
Children and adults who are severely dehydrated need treatment in a hospital emergency room, where they can receive salts and fluids through a vein (intravenously), rather than by mouth. Intravenous hydration provides the body with water and essential nutrients much more quickly than oral solutions do.
Most people who have shigella infection get better on their own and don't need to see a doctor. If you or your child has severe symptoms or a high fever, you may need treatment.
Before talking with your doctor, you may want to write a list of answers to the following questions:
During the physical exam, your doctor may press on various parts of your abdomen to check for pain or tenderness. He or she may also use a cotton swab to get a stool culture or send you home with instructions for collecting and transporting a sample of your stool so that it can be tested for evidence of infection.
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