Isolation of virus and analysis of surveillance among influenza-like cases in Maanshan Region

Objective The present study was conducted to clarify the epidemiological characteris-tics of influenza and the traits of dominant strains of influenza viruses in Maanshan Region from October 2005 to April 2006．Methods Influenza viruses were isolated by MDCK cell，and the subtypes were identified by hemagglutinafion inhibition test．Results During the period of October 2005 to April 2006．A total 0f 606 throat swabs of influenza-like patients were collected from 3 national influenza-monitoring hospitals in the Whole city，and the influenza viruses were positive in 69 strains with the isolation rate Of 11.4％．Of the 69 swains. 14 strains were influenza A1，and 55 strains were B/Victoria viruses with the isolation rates of 20.3％ and 79.7％ respectively．In-fluenza virus A3 and B/Yamagada were not found．The dominant strains were H1N1 and B/Victo-ria．Influenza A1 viruses were mainly isolated in January and February 2006．While B/Victoria viruses were isolated from February to April．Conclusion Among the infection population in Maanshan Region，the dominant strains of influenza viruses were A (H1N1) and B/Victoria type． Compared with the whole country，Influenza B/Victoria virus in Maanshan Region accounted for a higher proportion of the isolated viruses．