Press Release

Influenza activity remained high in Hong Kong

14 May 2012

The Centre for Health Protection (CHP) of the Department of Health today (May 14) called on the public to maintain vigilance against seasonal influenza as the latest surveillance data showed that local influenza activity remained at a high level.

The weekly number of influenza virus detections at the Public Health Laboratory Centre remained at high level in the past few weeks. The weekly number of influenza virus detections increased from 199 in the week ending April 14, 2012 to 442 in the week ending May 12, 2012.

During the past four weeks (week ending April 21 to week ending May 12), the circulating influenza viruses were mainly the influenza A (H3N2) virus (88.1%), followed by the influenza B (10.8%) and influenza A (H1N1) 2009 (0.8%) viruses.

The circulating influenza A(H3N2) virus was antigenically related but not identical to the current vaccine strain, A/Perth/16/2009 (H3N2)-like virus. Thus, the current vaccine is expected to offer a certain degree of protection against the circulating virus.

CHP has collaborated with the Hospital Authority (HA) and private hospitals to enhance surveillance during the winter peak influenza season about cases with influenza infection who required intensive care unit (ICU) admissions or died since January 13, 2012. From January 13 to noon on May 14, there were 159 cases (including 92 deaths) with ICU admissions or deaths with laboratory-confirmed influenza. During the enhanced surveillance period in the winter influenza season in 2011, the number was 123 cases (including 34 deaths). In view of the ongoing influenza activity, CHP will continue the enhanced surveillance in order to closely monitor the local situation in Hong Kong.

Influenza can cause medical complications, especially among vulnerable people such as the elderly, young children and those with chronic medical conditions. Influenza vaccination offers the best protection against influenza-related complications in these groups.

The public are reminded to take the following measures to prevent respiratory tract infection:

* Build up good body immunity by having a proper diet, regular exercise and adequate rest, reducing stress and avoiding smoking;
* Maintain good personal and environmental hygiene;
* Wash hands after sneezing, coughing or cleaning the nose;
* Maintain good indoor ventilation; and
* Avoid visiting crowded places with poor ventilation.

Members of the public, particularly young children, elderly people and those with chronic diseases, should wear face masks and consult their doctors promptly if they develop influenza-like symptoms.