In advisories issued on 7 and 10 October, the Singapore Ministry of Health (MOH) reported an increase in the number of acute diarrhoea cases seen by polyclinics over the past month. With the recent spate of diarrhoeal outbreaks in four schools (Ang Mo Kio Secondary, Stamford Primary School, Maris Stella and ACS(Independent)), the Ministry of Health has advised the public to be vigilant about diarrhoeal illnesses.
In two of the schools, Ang Mo Kio Secondary School and Stamford Primary School, the cause of the outbreaks has been identified to be noroviruses (other names: Norwalk-like viruses, caliciviruses) which cause stomach flu and viral gastroenteritis. Symptoms of norovirus illnesses include nausea, vomiting, diarrhoea, stomach cramps and abdominal pain. The disease usually lasts one to two days but in cases of excessive vomiting and diarrhea, dehydration may set in and patients could require special medical attention.
Symptoms and Contagiosity
- Noroviruses are very contagious and can be found in the faecal matter and vomit of infected persons.
- Infection occurs via :
- eating/drinking contaminated foods.
- touching contaminated objects and placing the objects or hands in the mouth.
- sharing food and/or eating utensils with infected persons.
- Symptoms, such as nausea, diarrhoea and stomach pains, appear within a day or two of exposure.
- Infected persons may be contagious for several days and up to as much as two weeks after recovery.
Prevention & Treatment
- There are currently no medication or vaccines against noroviruses.
- Antibiotics are ineffective against the viruses as they work only against bacteria.
- Infected persons should guard against dehydration by drinking replacement fluids.
- Practicing good hygiene, eating habits, cooking methods(such as avoiding raw food) and maintaining cleanliness reduce the chances of infection and contamination.
More information on noroviruses :
- United States Communicable Diseases Center (CDC)
- eMedicine - Norwalk Virus : Article by Todd Wills, MD