Hong Kong has entered the traditional peak period for seasonal influenza, with flu detections rising from 177 in the week ending March 6, to 268 in the week ending March 13.

The Centre for Health Protection today said influenza virus isolation in the Public Health Laboratory Centre showed a steady rise. Virus isolates are mainly either human swine influenza (49%) or influenza B (50%).

Reports of influenza-like illness outbreaks in institutions also surged from 24 in the week ending March 13, to 31 from March 14 to 18.

The consultation rate for influenza-like-illness among sentinel private doctors increased in recently. During the week ending March 13, the consultation rate for influenza-like-illness at private clinics was 51 per 1,000 consultations. 

The centre's surveillance system also showed high seasonal activity of respiratory syncytial virus. The number of respiratory syncytial virus detections in the week ending March 13 was 134. The figure is consistent with the trend recorded in the past few years.

The centre will closely monitor the situation and has sent letters to doctors, schools and institutions alerting them to the upcoming flu season and providing advice on prevention and control.