Singapore carried out island wide cleaning in schools on Sunday after four schools had staff and students coming down with possible gastric flu.
Ang Mo Kio Secondary School was the first school that reported 300 students sick last month.
Over the last few days, more that 200 students at Stamford Primary and 20 to 30 students at Maris Stella Primary and ACS ( Independent) also showed symptoms of gastric flu, such as vomiting and diarrhea, according to Channel NewsAsia reports.
To prevent further outbreaks, Singapore's Education Ministry has asked all schools to intensify the cleaning regime of school premises, particularly in the canteens and toilets.
Source: Xinhua