CHP reports latest investigation of outbreak of acute gastroenteritis at primary school in Kowloon Tong

     The Centre for Health Protection (CHP) of the Department of Health (DH) today (March 3) reported the latest progress of its investigation into an outbreak of acute gastroenteritis (AGE) at a primary school in Kowloon Tong, and again reminded the public and management of institutions and schools to maintain personal and environmental hygiene against AGE.

     The CHP yesterday (March 2) reported the case after receiving notification from CCC Kei Wa Primary School (Kowloon Tong) on an AGE school outbreak. The CHP's epidemiological investigations revealed that a student developed vomiting and diarrhoea earliest on February 28 and had vomited in a classroom that day. The patient sought medical attention at a private hospital and tested positive for norovirus upon laboratory testing. Subsequently, students in that classroom and neighbouring classrooms on the same floor developed similar symptoms on March 1 and 2. The CHP also confirmed that the affected students did not consume common food or meal boxes and the investigation results revealed that there was an outbreak of AGE caused by norovirus on that floor, with a higher chance of person-to-person transmission or environmental contamination.  The CHP has ruled out that the outbreak involved food poisoning.

     Following yesterday's announcement that the outbreak involved 27 students, the CHP identified 13 additional affected students as at noon today, comprising 11 boys and two girls aged 6 to 7 years, who developed vomiting and diarrhoea. All patients are in a stable condition. This brings the total number of students affected in that school to 40. Due to the person-to-person transmission of the norovirus in the school following the incident of vomiting in the classroom and environmental contamination, the number of affected students may increase in the coming days subject to the effectiveness of environmental disinfection at the school.

     There is yet to be an outbreak among the classes located on other floors of the school. Officers of the CHP have already conducted a site visit and stressed to the staff of the school the importance of thorough environmental disinfection, proper disposal of vomitus, and personal and environmental hygiene. The school has been put under medical surveillance. Investigations are ongoing.

     A spokesman for the CHP said that AGE is commonly caused by virus, e.g. norovirus and rotavirus. Infection can be transmitted by direct contact with the vomitus or excreta of infected persons and with contaminated objects or aerosol spread with contaminated droplets of splashed vomitus. The spokesman stressed that proper management and adequate disinfection of vomitus and faecal matter is of crucial importance in preventing and controlling the spread of the disease.

     A spokesman for the CHP advised members of the public to take heed of the following preventive measures against gastroenteritis:
  • Ensure proper personal hygiene;
  • Wash hands thoroughly before handling food and eating, after using the toilet or after changing diapers;
  • Wear gloves when disposing of vomitus or faecal matter, keep other people away from the contaminated area throughout the disinfection procedure and wash hands afterwards;
  • Clean and disinfect contaminated neighbouring areas (within two metres from the edge of the vomitus) or items promptly and thoroughly with diluted household bleach (by adding one part of bleach containing 5.25 per cent sodium hypochlorite to 49 parts of water). Wash hands thoroughly afterwards;
  • Maintain good indoor ventilation;
  • Pay attention to food hygiene;
  • Use separate utensils to handle raw and cooked food;
  • Avoid food that is not thoroughly cooked;
  • Drink boiled water; and
  • Do not patronise unlicensed food premises or food stalls.

     ​​The public may visit the CHP's website ( or call the DH's Health Education Infoline (2833 0111) for more information.

Ends/Friday, March 3, 2023
Issued at HKT 18:50