Shigella sonnei

bacterium

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Last updated

July 15, 2026

Quick Summary

Shigella sonnei is a species of rod-shaped bacteria belonging to the genus Shigella, which are common inhabitants of the human intestinal tract. These bacteria are gram-negative, non-spore-forming, and nonmotile.1

Shigella species are the cause of bacillary dysentery, also known as shigellosis. This infectious disease is characterized by inflammation of the intestine, abdominal pain, and diarrhea that can contain blood and mucus. While S. dysenteriae produces a potent exotoxin and causes the most severe illness, S. sonnei and S. flexneri are also implicated in causing dysentery.123

Shigellosis is transmitted through the fecal-oral route, often via contaminated food or water, and is more prevalent in areas with poor sanitation and overcrowding. Diagnosis is typically made through stool cultures, and treatment involves antibiotics.3

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dysentery
flexneri, S. sonnei, and S. boydii are other Shigella bacilli that cause dysentery. Other types of bacterial infections, including salmonellosis (caused by Salmonella) and campylobacteriosis (caused by Campylobacter), can produce bloody stools and are sometimes also described as forms of
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flexneri, S. sonnei, and S. boydii are other Shigella bacilli that cause dysentery. Other types of bacterial infections, including salmonellosis (caused by Salmonella) and campylobacteriosis (caused by Campylobacter), can produce bloody stools and are sometimes also described as forms of
Read More