Shigellosis

Shigellosis is an infection of the bowel caused by the bacteria Shigella.

How it spreads

Spread can occur by eating food or drinking water that has been contaminated by very small amounts of faeces from infected people.

Spread can also occur through oral-anal contact.

Symptoms

Symptoms generally develop between 1 to 3 days after becoming infected but it may take up to a week for symptoms to appear.

Most people who are infected with Shigella develop diarrhoea (sometimes with blood or mucus), fever, vomiting and stomach cramps.

Typically, the illness lasts 3 to 4 days but may last longer, particularly in the very young, elderly and malnourished people,

Some infected people only have a very mild illness or no symptoms at all.

Infectious period

While the Shigella bacteria remain in their faeces, infected people can pass the infection on to others. This is usually while they are ill and up to 4 weeks after symptoms have resolved. Infected people without symptoms can transmit the infection and can occasionally shed Shigella in their faeces for many months.

Who is at risk

The most severe infections occur in the very young, the elderly and malnourished people.

Children who attend childcare facilities are at greater risk of infections spread through faecal contamination. Spread occurs when children share toys or food that have become contaminated and place it in their mouths. Particular care has to be taken wherever there are children in nappies.

Travellers to developing countries or to remote communities where sanitation and hygiene are poor are at higher risk of contracting diarrhoeal illness.

Men who have sex with men are more at risk of shigellosis.

Treatment

Management focuses on preventing and treating dehydration caused by vomiting or diarrhoea. Anyone with vomiting or diarrhoea should drink extra fluids to avoid dehydration. Rehydration therapy with oral glucose/electrolyte solution is particularly effective. If children refuse this solution, diluted fruit juice may be given (1 part juice to 4 parts water).

Babies should continue to be offered their normal feeds plus extra fluids in between feeds.

Children with diarrhoea, who vomit or who refuse extra fluids should see a doctor. Anyone with prolonged or severe diarrhoea or who have symptoms that concern them, should see a doctor.

Medicines to prevent vomiting or diarrhoea should not be given, especially to children, except when prescribed by a doctor.

When the diagnosis of shigellosis is confirmed, antibiotics may be prescribed. This can reduce the risk of complications and the spread of infection to others.

How shigellosis can be prevented

Good hygiene is the best way to prevent shigellosis.

Hands should be washed thoroughly with warm soapy water:

  • after going to the toilet
  • before preparing or handling food
  • after every nappy change
  • after changing soiled linen.

Other measures include:

  • never changing nappies on tables or counters where food is prepared or eaten
  • cleaning change areas with warm soapy water and disinfectant after every nappy change
  • cleaning books, toys, equipment, furnishings, floors and toilets regularly (including toilet door handles)
  • washing raw fruit and vegetables carefully before eating.

How it can be controlled

Anyone with diarrhoea should not attend childcare/school for 24 hours after the diarrhoea has ceased.

People with diarrhoea should not prepare or handle food that will be eaten by others.

Anyone with diarrhoea should not swim, wade or paddle in public pools.

Doctors and public health workers are interested in preventing outbreaks of diarrhoea. If there are 2 or more cases of diarrhoea in a group, these should be reported to the local Centre for Disease Control.

Contact

For more information contact your nearest Centre for Disease Control.

Last updated: 27 June 2017