Detection of Influenza Virus Infections

Yi-Syue Li

2008 Vol.24 NO.9

Correspondence Author: Yi-Syue Li


From late December 2007 to early January 2008, an outbreak of upper respiratory tract infection (URI) was reported in an institution for the disabled in Taipei County. A total of 36 people, including one health care worker and 35 residents, developed symptoms of URI and showed signs of influenza. Respiratory specimens were taken from 27 patients and tested for influenza viruses by National Influenza Center and CDC Collaborating Lab. 16 (59.3%) influenza A viruses were found out of the samples collected. It was interesting to note that the outbreak of epidemic influenza infection occurred among residents with high influenza vaccination rates (95.1%). Further examination with phylogenetic tree analysis and HI tests told us why this is so; the influenza virus A/H3 isolated from this incident showed antigenic difference from the A/H3 strain in the trivalent vaccine for the 2007-2008 season.
Keywords: populous institution, clusters incident, influenza virus, vaccine, HI test