Influenza pandemic plan: integrated wild bird/domestic avian/swine/human flu surveillance systems in Taiwan

Abstract Background : Integrated virological surveillance systems along the transmission chains from animals to humans in areas with large swine/chicken/duck populations and numerous wild migrating birds grasps the frontline timing to detect novel flu viruses. Materials and methods : Animal and human virological surveillance systems have been established to monitor evolutional changes of flu viruses in the same and different hosts/geographical areas over years. Selected sentinel physicians collected specimens from influenza-like patients at local clinics/hospitals in: (a) counties with high populations of swine/avian/wild birds in Taiwan and (b) Kinmen islet—closest to China. Results : Novel animal and human influenza viruses (swine H1N2, avian H5 and H7 and human H3N2 within the lineage of A/Fujian/411/2002) were detected in 2002. However, subtypes of H5, H7 and H9 were not found in human isolates in Taiwan till Oct. 2003. Sentinel physician and school absenteeism surveillance systems were more sensitive than human laboratory and respiratory syndromic surveillance systems. Variation patterns of antigenic sites of HA1 in human versus animal flu A viruses were also quite different. Conclusion : The integrated surveillance is very useful in disease control and understanding conditions for the emergence of novel flu viruses with pandemic potential.