Background

• Shigella dysenteriae type 1 (SD1) is the most common cause of enteric infections and is transmitted from person-to-person through faecal-oral spread.
• Large scale outbreaks may be caused by SD1 with up to 30% of populations infected. The case fatality rate may approach 20% among young children and elderly persons with severe dehydration.
• The incubation period is from 1 to 4 days.
• Clinical illness is characterized by acute fever and bloody diarrhoea, and can also present with systemic symptoms and signs as well as dehydration especially in young children.
• Risk factor: overcrowded areas with unsafe water and poor sanitation (for example, refugee and famine populations).
• SD1 is frequently resistant to multiple antibiotics including trimethoprim-sulfamethoxazole.
• Enterohaemorrhagic and enteroinvasive E. coli and other bacteria or parasites such as Entamoeba histolytica may also cause bloody diarrhoea.