Influenza Activity in Taiwan: 2005/2006 Season

Chiu-wen Chang

2007 Vol.23 NO.9

Correspondence Author: Chiu-wen Chang


from Chinese version, pp,489-504
In Taiwan, surveillance of influenza is based on a multi-sources surveillance portal to collect timely and comprehensive data on influenza activity. The portal consists of the ‘Sentinel Surveillance System’, ‘Laboratory Surveillance System’, ‘Notifiable Diseases/Syndromic Surveillance System’, ‘School-based Surveillance System’, ‘Surveillance System for Populous Institutions’ and ‘Symptom Surveillance System’. This report collects and analyzes influenza activity for the 2005/2006 influenza season in Taiwan. This season started in the first week of July 2005 and ended in the last week of June 2006, with peak activity occurring between week 50/2005 and week 10/2006. In comparison with the previous 2 influenza seasons, Taiwan experienced a low level of influenza activity during 2005/2006 influenza season. The percentage of patient visits to sentinel physicians for ILI peaked at 4.13% (week 6, 2006). During the previous two influenza seasons, the peak percentages for such visits ranged between 5% and 6.1%. Additionally, 792 cases of laboratory-confirmed influenza-like illness were reported. By antigenical analysis, 745 were identified as influenza A(491 were A/H1, 253 were A/H3) strains and 47 as influenza B viruses. Influenza A/New Caledonia/20/99(A/H1N1) viruses predominated with peak activity occurring during February and March 2006. The majority of ILI clusters were reported from schools, and the main pathogen was confirmed to be influenza A virus. During 2005/2006 influenza season, 70 complicated influenza cases have been reported. Among these, 16 were confirmed and 3 deaths have been reported. In conclusion, multi-sources surveillance offers not only the opportunity to provide early warning of influenza activity but also a wealth of useful information for policy making.
Key words: influenza、flu season、ILI、Flu virus、surveillance system