Symptoms of a Shigella infection include diarrhea, fever, stomachache, and tenesmus.
If you have a Shigella infection, you may experience the following signs and symptoms about one to two days after the exposure:
- Diarrhea or loose stools that may be blood-stained
- Fever
- Stomachache
- Tenesmus (a frequent feeling or urge that you need to have a bowel movement even if you just emptied your bowels)
Some people who have been exposed to a Shigella infection could be asymptomatic.
Rarely, some people may experience the following symptoms after a Shigella infection:
- Post-infectious arthritis:
- Seen in about two percent of the people infected with a particular Shigella species called Shigella flexneri.
- Post-infectious arthritis may affect people who are genetically predisposed to this condition.
- The symptoms include joint pain and swelling, painful urination, and eye irritation.
- These symptoms may last for months or years and may even progress to chronic arthritis.
- Seizures:
- They generally occur in children particularly those with a high fever.
- Lab reports may show deranged electrolyte levels (serum sodium, potassium, and calcium).
- The exact cause of seizures following Shigella infections is not well understood.
- Generally, the seizures subside without any treatment.
- Bloodstream infections (bacteremia):
- Generally seen in people with weak immunity, such as people with human immunodeficiency virus infection, uncontrolled diabetes, or cancer, or those who are severely malnourished.
- The Shigella bacteria damages the lining of the gut and enters the bloodstream via the leaky gut, causing widespread infection.
- The affected person may have a fever, chills, rapid heartbeat, trouble breathing, confusion, or fainting episodes.
- Hemolytic uremic syndrome:
- Caused by a toxin called Shiga toxin, which is produced by Shigella dysenteriae.
- The toxin damages red blood cells (hemolytic anemia) and causes low platelet count (thrombocytopenia) and acute kidney failure.
- The person may have bloody diarrhea, abdominal cramps, fever, vomiting, bruises, difficulty breathing, extreme fatigue, swelling over the feet, ankles, and legs, and bleeding from the nose or mouth.
What is Shigella?
Shigella is a type of bacteria that causes infection of the gut called shigellosis.
Several species of Shigella may cause gut infections, such as:
- Shigella dysenteriae (rare in the United States but causes deadly shigellosis outbreaks in developing countries)
- Shigella sonnei (causes most of the shigellosis cases in the United States)
- Shigella flexnerii (the second most common cause of shigellosis in the United States)
Shigella can be found in water contaminated with infected sewage, which may then contaminate food products rinsed in the water. Crops grown in polluted water can carry the bacteria as well. Flies may carry the bacteria if they touch feces and contaminate food.
The infection is generally spread by consuming such contaminated water or food. Infection may spread by touching the mouth or eating with dirty fingers that have touched anything soiled with feces, such as bathroom fixtures, toilet seats, toys, and used diapers.
When do you seek medical help?
Usually, the symptoms of Shigella infection go away in five to seven days. Some people, however, may experience symptoms for four or more weeks, whereas others may take months to get their bowel habits back to normal.
One must seek medical attention if they experience any of the following symptoms:
- Fever
- Severe abdominal pain or cramps
- Bloody diarrhea
- Dehydration (seen as sunken eyes, dry mouth, lack of tears, dry diapers, or lightheadedness)
- Severe fatigue or weakness
- Seizures
- Bruising or bleeding from mouth or nose
- Blood in the urine
- Swelling over the feet, ankles, or legs
- Confusion or altered mental status
- Difficulty breathing