What are the four types of Shigella?

What are the four types of Shigella?

The four species of Shigella are:

  • Shigella sonnei (the most common species in the United States)
  • Shigella flexneri.
  • Shigella boydii.
  • Shigella dysenteriae.

What is the difference between the types of Shigella?

The genus Shigella is differentiated into four species: S dysenteriae (serogroup A, consisting of 12 serotypes); S flexneri (serogroup B, consisting of 6 serotypes); S. boydii (serogroup C, consisting of 18 serotypes); and S sonnei (serogroup D, consisting of a single serotype).

What is the difference between Shigella and shigellosis?

Shigella bacteria cause an infection called shigellosis. Most people with Shigella infection have diarrhea (sometimes bloody), fever, and stomach cramps. Symptoms usually begin 1–2 days after infection and last 7 days. Most people recover without needing antibiotics.

What is the most common cause of shigellosis?

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.

Can Shigella be cultured?

Because the Shigella are members of the same family as E. coli, most of the culture media and techniques used for growth and maintenance of E. coli work well for the Shigella species.

Where is Shigella most commonly found?

Shigella is found in the stool (feces) of infected people, in food or water contaminated by an infected person, and on surfaces that have been touched by infected people. Shigellosis often occurs in toddlers who are not fully toilet-trained.

How many serotypes of Shigella are there?

Overview of Shigella Subgroups The genus Shigella has 4 species or subgroups (A, B, C, and D) and 43 serotypes (Table A). Subgroups A, B, C, and D have historically been treated as species: subgroup A is referred to as S. dysenteriae; subgroup B as S. flexneri; subgroup C as S.

How is shigellosis diagnosed?

Infection is diagnosed when a laboratory identifies Shigella in the stool (poop) of an ill person. The test could be a culture that isolates the bacteria or a rapid diagnostic test that detects genetic material of the bacteria.

What are the symptoms of shigellosis?

Symptoms of shigellosis include diarrhea (often bloody), abdominal pain, stomach cramps, and fever. Sometimes people infected with Shigella have no symptoms at all, but can still pass the bacteria to others. Symptoms usually begin 1 to 3 days after being exposed to Shigella.

Does Shigella grow on blood agar?

In Blood Agar medium, the Shigella dysenteriae shows gamma hemolysis i.e. no hemolysis occurs on blood agar medium, the colonies are grayish-white and grows well.

How do they test for Shigella?

To confirm the diagnosis of shigellosis, doctors take a sample of stool and send it to a laboratory to grow (culture) and identify the bacteria. Bacteria are also tested to see which antibiotics are effective (a process called susceptibility testing.