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 small amounts of faeces from infected people.
It can also occur through oral-anal contact.
Who is at risk
The most severe illness is seen in children, the elderly and those with impaired immune systems.
Children who attend childcare facilities are at greater risk of infections due to 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.
Those also at higher risk include:
- travellers to developing countries where sanitation and hygiene standards are poor
- men who have sex with men.
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.
Treatment
If shigellosis is confirmed, antibiotics may be prescribed to reduce the risk of complications and the spread.
Other treatment solutions mainly focuses on preventing and treating dehydration caused by vomiting or diarrhoea.
To avoid dehydration, anyone with vomiting or diarrhoea should drink extra fluids.
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.
Medicines to prevent vomiting or diarrhoea should not be given, especially to children, except when prescribed by a doctor.
When to see a doctor
Children who refuse extra fluids should see a doctor.
Additionally, anyone with the following should also see a doctor:
- prolonged (>3 days) or severe diarrhoea
- blood in their stools
- people concerned about their symptoms.
Control measures
People with vomiting or diarrhoea should not:
- prepare or handle food that will be eaten by others
- go back to work, school or childcare until 48 hours after diarrhoea and vomiting have ceased
- 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 in a group, these should be reported to the local Centre for Disease Control.
Prevention
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.
Information for health professionals
To find out more, go to the NT Health website.
Contact
Contact your nearest Centre for Disease Control on the NT Health website.