Sequencing Analysis of the Viruses Responsible for Two Recent Clustering Outbreaks of Type B Influenza in Ilan Area

Shu-Chun Chin

2007 Vol.23 NO.6

Correspondence Author: Shu-Chun Chin


In early November 2006, there were two outbreaks of epidemic influenza infections in Ilan County and centered at two schools: one junior high school in Chiaohsi Township, and another preliminary school in Yuanshan Township. The high infection rate among students in these two schools together with the apparent clustering nature of the outbreaks has made the local health authority became quite alarmed and made an extra effort in collecting many specimens from the infected, which were then sent over to Taiwan CDC Laboratory in Nangang District, Taipei City. Working at the laboratory, we were instructed to verify the type of the specimen (Type B, decided by the local hospitals attending the sick students) and also find out their subtype classification and other characteristics. With those collected specimens, apart from doing a standard procedure of real-time RT-PCR for clinical diagnosis, we have also conducted a cell culture trial of the virus isolate, followed by examining the antigenicity of the virus, and sequencing certain gene fragments of its surface antigen HA and NA, in order to figure out exactly what sort of flu virus was responsible for the two large clustering outbreaks. The rationale behind this study was that we believed the