Bacillary Dysentery
3 May 2024
Causative agent
Bacillary dysentery, also known as shigellosis, is an intestinal infection caused by Shigella bacteria (including S. sonnei, S. flexneri, S. boydii and S. dysenteriae).
Clinical features
Infection by Shigella can be asymptomatic or only cause mild symptoms. For patients who develop bacillary dysentery, they often present with fever, diarrhoea, abdominal pain, nausea and vomiting. The stool may contain blood and mucus. Rare complications include reactive arthritis and acute kidney disease.
Mode of transmission
Bacillary dysentery is transmitted mainly through the faecal-oral route, such as physical contact with the faecal material of a patient or carrier (including diaper-changing and oral-anal sex), or indirectly through consumption of contaminated food and water. It just takes a small number of the bacteria to become infected. The disease is highly contagious and many outbreaks occur in childcare settings and schools.
Risk factors
Young children, travellers to developing countries, homeless people and men who have sex with men are more likely to acquire bacillary dysentery. People who have weakened immune systems may develop a more serious illness.
Incubation period
The incubation period is usually 1 - 3 days, but can be up to 7 days.
Management
Infected persons in schools or institutions should be isolated. They should observe personal hygiene to avoid infecting other persons. Treatment includes fluid replacement and antibiotics.
Prevention
1. Maintain good personal hygiene- Perform hand hygiene frequently, especially before handling food or eating, and after using the toilet or handling faecal matter.
- Wash hands with liquid soap and water, and rub for at least 20 seconds; then rinse with water and dry with a disposable paper towel or hand dryer. If hand washing facilities are not available, or when hands are not visibly soiled, hand hygiene with 70 to 80% alcohol-based handrub may be an effective alternative.
- Refrain from work or school, and seek medical advice when suffering from gastrointestinal symptoms such as diarrhoea.
- Adopt the 5 Keys to Food Safety in handling food, i.e. Choose (Choose safe raw materials); Clean (Keep hands and utensils clean); Separate (Separate raw and cooked food); Cook (Cook thoroughly); and Safe Temperature (Keep food at safe temperature) to prevent foodborne diseases.
- Drink only boiled water from the mains or bottled drinks from reliable sources.
- Avoid drinks with ice of unknown origin.
- Purchase fresh food from hygienic and reliable sources. Do not patronise illegal hawkers. In general, you can eat fruits with skin after thorough washing. However, if you would like to reduce the risk of illness especially when you travel abroad, peel the raw fruits before you eat and do not eat the peelings.
- Eat only thoroughly cooked food.
- Exclude infected persons and asymptomatic carriers from handling food and from providing care to children, elderly and immunocompromised people.
