Hong Kong has entered traditional peak season for seasonal influenza

18 Mar 2010

The Centre for Health Protection (CHP) of the Department of Health today (March 18) called on members of the public to take precautionary measures against seasonal influenza, which consists mainly of human swine influenza and influenza B.

A CHP spokesman said that the latest surveillance data showed an increasing number of influenza isolates, which signal that Hong Kong has entered the traditional peak season for seasonal influenza.

Influenza virus isolation in the CHP's Public Health Laboratory Centre (PHLC) showed a steady rise. A total of 268 influenza detections were recorded last week (from March 7 to 13) as compared with 177 influenza detections from February 28 to March 6. Virus isolates are mainly either human swine influenza (49%) or influenza B (50%).

There has been an increase in the reports of influenza-like-illness (ILI) outbreaks in institutions, from 24 in the week ending March 13 to 31 in the past five days (March 14 – 18). The consultation rate for ILI among sentinel private doctors has also increased in the past few weeks. During the week ending March 13, the consultation rate for ILI at private clinics was 51 per 1,000 consultations.

At the same time, CHP's surveillance system also showed high seasonal activity of respiratory syncytial virus (RSV). The number of RSV detections in the week ending March 13 was 134. The figure is consistent with the trend recorded in the past few years.

The spokesman said, "As a preventive measure, the CHP has sent letters to doctors, schools and institutions alerting them of the upcoming flu season and providing advice on prevention and control.

"CHP will send letters again reminding them to be vigilant against respiratory infection. The influenza situation will be closely monitored as the flu season progresses."

Members of the public are reminded to take the following measures to prevent influenza and other respiratory illnesses:

* To build up good body immunity by having a proper diet, regular exercise and adequate rest, reducing stress and avoiding smoking;
* To maintain good personal and environmental hygiene;
* To wash hands after sneezing, coughing or cleaning the nose;
* To maintain good ventilation; and
* To avoid visiting crowded places with poor ventilation.

People, particularly young children, elderly people and those with chronic diseases, should wear face masks and consult their doctors promptly if they developed influenza-like symptoms.