What disease do Shigella cause?

• Bacillary dysentery(members of its family)
• Shigellosis
• renal Failure, ischemia and hemorrhagic colitis(by shiga toxin)
• Ulceration
• rarely bacteriemia(bacteria entering the blood stream) or sepsis(condition that happens when the body’s immune system has an extreme response to an infection)

What family does the genus Shigella belong to?why?

Enterobacteriaceae, bc they have similar DNA sequence(DNA homolgy)

With which genera has Shigella traditionally been grouped?

• Salmonella
• Yersinia

They consider Shegilla a sub species of what?

Escherichia

In which populations are dysentery outbreaks commonly associated?

• Families
• Cruise ships
• Mental hospitals
• Day-care facilities
• Prisoners

How many Shigella organisms are needed to cause disease?

Ingestion of as few as 100 - 200 organisms.

How long can Shigellae survive in milk, eggs, cheese, or shrimps?

Up to 30 days.

What percentage of shigellosis infections occur in children under 15 years?

70% of infections.

What do Shegilla needs to have in order to invade host cells

A 220-kb plasmid encoding 4 proteins: IpaA, IpaB, IpaC, IpaD.

What role does IpaD play in Shigella infection?

IpaD acts as an adhesion allowing phagocytosis.

Where is the host cell receptor for IpaD expressed?

On the basolateral pole(interior side of abdomen) of enterocytes(epithelial lining of intestine)

What is Shiga neurotoxin identical to? who produces it?

Verotoxin-1 produced by enterohemorrhagic E. coli strains of E.coli

What are the dysentery like diseases that resemble that dysentery due to shigella

• Enteroinvasive E. coli
• Campylobacter jejuni
• parasite Entamoeba histolytica.