Shigellosis Bacillary Dysentery

What is Shigellosis?

Shigellosis is an acute bacterial infection that is caused by a group of bacteria known as shigella.  There are various kinds of shigella in different parts of the world.  They are generally found in contaminated food and cause severe diarrhoea (dysentery). The shigella bacteria are probably responsible for diarrhoeal disease in developing countries where food handling procedures often lead to contamination.

How do you get Shigellosis?

Shigella bacteria are almost always transmitted through consumption of contaminated food.  It may also be found in water polluted with human waste. The bacteria can be transmitted frequently from person to person through poor hygiene and then hand to mouth contact.

Susceptibility and Resistance

All people, especially children, are susceptible to infection with shigella bacteria.

Incubation Period

The incubation period for Shigellosis is 1-7 days.

What are the Symptoms?

The illness begins with fever, nausea, vomiting and abdominal cramps. Loose bowel movements and sometimes watery diarrhoea often include blood and mucous in the stool. Some strains of this bacterium can cause serious illness, such as generalised toxicity, intestinal perforation and kidney damage. Mortality rates can be as high as 20 percent without treatment. The illness usually lasts about 4 to 7 days.

Preventative Measures

Practicing careful personal hygiene, e.g., frequent hand washing, especially after being in contact with an infected individual is essential. Avoiding consumption of contaminated food and water (particularly from street vendors) will also reduce the risk of infection.


Prompt treatment with antibiotics shortens the severity and duration of the illness.


Where Does It Commonly Occur?

The shigella bacteria that cause shigellosis are found worldwide.