The Department of Health has called on people to be vigilant in maintaining good personal hygiene as the peak season for viral gastroenteritis draws near.

Two recent gastroenteritis outbreaks and an increasing number of patients with acute diarrhoeal diseases since mid-October suggest the onset of the peak period for the illness.

Department Consultant Dr Thomas Tsang said test results showed that the two outbreaks are related to the Norwalk-like virus. Guangdong health authorities are also reporting recent cases caused by the virus.

Dr Tsang said this proves the virus is more active in winter and the outbreaks are a regional phenomenon for southern China.

As the illness is common in Hong Kong and highly infectious, the department has alerted all schools, childcare centres, and homes for the aged to take extra precautions. Doctors have also been reminded to advise patients on preventive measures.

Dr Tsang said there were 39 cases involving 892 people reported in institutions last year, while 41 have been reported so far this year, affecting about 1,000 people.

To prevent viral gastroenteritis, people should:

* wash hands thoroughly before handling food and eating, and after going to the toilet;

* wear gloves while disposing of vomit and faeces, and wash hands afterwards;

* clean and disinfect contaminated area and items promptly and thoroughly with household bleach diluted at a ratio of 1 to 49 units of water;

* sick students should rest at home and not go to school;

* maintain good indoor ventilation; and,

* eat only thoroughly-cooked food, particularly seafood and shellfish.

People can obtain health advice on preventing the virus at the department's website, or by calling its Central Health Education Unit hotline on 2833 0111.