Shigella Infection (Shigellosis)
What is Shigella infection?
Shigellosis, or Shigella infection caused by Shigella bacteria, is a disease that affects your digestive system. It produces stomach pain, diarrhea and fever in people who are infected. Shigella is very contagious. There are various types in the Shigella bacteria group.
You can get shigellosis by eating contaminated food or drinking contaminated water. If you swim in contaminated water, you may get shigellosis by accidentally swallowing water that you’re swimming in.
Shigella infection, a type of food poisoning, may also be called bacillary dysentery. Dysentery is a word for diarrhea that contains blood or mucus.
Who does Shigella infection affect?
Anyone can be infected with Shigella, but it often occurs in regions with poor sanitation or in crowded places, such as schools, day care centers and nursing homes. Younger children are more likely to be infected because they often put their hands in their mouths.
How common is Shigella infection?
Shigellosis is a worldwide problem, with about 188 million cases per year that result in about 1 million deaths per year. In developed countries, there are about 1.5 million cases per year. In the U.S., there are approximately 450,000 cases every year.
Symptoms and Causes
What causes shigellosis?
Shigella bacteria are usually found in the stool (feces, or poop) of people who are infected. The bacteria are spread when someone comes into contact with the stool of an infected person or comes into contact with an item that’s been contaminated with the stool or the bacteria.
People get shigellosis by eating food or drinking water that has been contaminated, or through sexual contact with an infected person. Many different foods can be contaminated, but Shigella is found typically in uncooked vegetables or shellfish.
What are the symptoms of Shigella infection?
Common signs and symptoms of shigellosis include:
- Diarrhea, which can be watery, bloody and/or contain mucus or pus.
- Stomach pain and cramps.
In some cases, people who are infected with the Shigella bacteria don’t have symptoms but are still contagious.
Diagnosis and Tests
How is shigellosis diagnosed?
Your provider may diagnose you with Shigella infection on the basis of your symptoms. However, testing a stool sample for the presence of the bacteria will let you know for sure.
Management and Treatment
How is shigellosis treated?
Treatment for Shigella depends on how severe it is.
Self-care at home
If your symptoms are mild, you can treat it with rest and by drinking fluids to prevent dehydration (a dangerous loss of water in your body).
You can also take bismuth subsalicylate (Pepto-Bismol®) for the diarrhea. Don’t take loperamide (Imodium®) or diphenoxylate with atropine (Lomotil®) because these drugs slow bowel function and keep the bacteria in your system.
In more severe cases of shigellosis, and for people with weak immune systems, doctors may prescribe an antibiotic to treat the infection. Your provider may prescribe ciprofloxacin or azithromycin.
Make sure you follow directions and take all of the antibiotics even if you start feeling better before they’re gone.
What are the complications or side effects of shigellosis?
Shigellosis can cause dehydration because of the diarrhea. This condition can be very dangerous for elderly people and babies.
Sometimes, infection with Shigella bacteria can produce these complications:
- Bloodstream infections.
- Seizures (in children).
- Post-infection arthritis, which is also called Reiter’s syndrome or reactive arthritis. If you develop this after shigellosis, you’ll have achy joints, irritated eyes and pain when you urinate (pee).
- Hemolytic uremic syndrome, a condition that affects small blood vessels and that can cause anemia.
Can shigellosis be prevented?
You can lessen your risk of getting or spreading shigellosis in the following ways:
- Wash your hands with soap and water thoroughly and often, especially before and after eating, after using the bathroom and changing diapers, before preparing food, and after coming into contact with an infected person.
- Wash foods well and cook them well.
- Avoid swallowing water in pools, lakes or ponds.
- Throw away soiled diapers in a lined garbage can with a lid.
- Follow safe food and water instructions when traveling in other countries.
- Wait for a week after your partner has recovered from diarrhea before engaging in sexual activities.
Researchers are working on vaccines against Shigella bacteria but haven’t developed one yet.
Outlook / Prognosis
What is the outlook if I have shigellosis?
Most people with shigellosis feel better in four to seven days, but they may still be contagious for weeks after they recover. People who have severe infections may be sick for three to six weeks. Complications are rare, but they can happen.
When should I call the doctor about shigellosis?
Call your doctor if you or someone in your family develop bloody diarrhea, fever or severe stomach cramps. If you have shigellosis and cannot keep down enough fluids to avoid dehydration, let your provider know.
How do I take care of myself?
It’s important to keep hydrated if you have shigellosis. You can drink water, beverages that add electrolytes back to your body or eat Popsicles®.
Frequently Asked Questions
What foods cause Shigella infection?
You’re most likely to be infected with Shigella from raw foods that you eat. These include salads, fruits and vegetables that may have been grown in soil contaminated by human feces. However, you can get Shigella from any food prepared by someone with unsanitary habits (unclean hands).
Can you get Shigella infection more than once?
It’s unlikely, but it’s possible to get shigellosis more than once.
A note from Cleveland Clinic
Shigellosis, or infection with Shigella bacteria, causes watery and possibly bloody diarrhea. The best way to prevent getting or spreading Shigella is to follow good hand washing practices. Contact your healthcare provider if you’re in extreme pain or have a high fever. You can rest at home and keep drinking fluids like water to stay hydrated. You may need antibiotics, but most people recover completely from shigellosis.
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