Author(s)

Day-Yu Chao^1*, Kuang-Fu Cheng², Yu-Hsin Liao¹, Ming-Tsan Liu³, Ying-Hen Hsieh^4,5, Tsai-Chung Li^2,4, Trong-Neng Wu^4,5, Chiu-Ying Chen⁵

¹Graduate Institute of Microbiology and Public Health, College of Veterinary Medicine, National Chung-Hsing University, Taichung.
²CMU Biostatistics Center, China Medical University, Taichung.
³National Influenza Center, Center for Disease Control, Taipei City.
⁴Graduate Institute of Biostatistics, China Medical University, Taichung.
⁵Department of Public Health, China Medical University, Taichung.

While Influenza B viruses currently circulating worldwide are of two distinct evolutionary hemagglutinin lineages, current trivalent inactivated influenza virus vaccines (TIV) contain only a single component. Single doses of TIV containing B antigen of B/Florida/4/2006 (Yamagata-like) or B/Brisbane/60/2008 (Victoria-like) were administered during 2008/2009 and 2009/2010 influenza seasons, respectively. The objective of this study was to evaluate the immunological response against different lineages of B antigens in school-aged children. A non-randomized sero-epidemiological study was conducted and the immunogenicity responses based on sero-protection rate and geometric mean titre ratio (GMTR) of hemagglutination inhibition (HI) antibodies were measured before and after immunization as well as post-influenza season. Our results suggested that school-aged children under the age of 9 years receiving TIV vaccination induced and retained higher level of sero-protection rate (66.7% and 69% for the 2008-09 and 2009-10 season, respectively) to the homologous lineage than the heterologous lineage post-vaccination (19.4% and 27.6% for the 2008-09 and 2009-10 season, respectively). The need for the quadrivalent TIV by including both lineages of influenza B viruses is recommended in this study, particularly for children under the age of 9 years.

Children, Immunology, Influenza, Trivalent Inactivated Vaccine (TIV), Yamagata/Victoria Lineage

Chao, D. , Cheng, K. , Liao, Y. , Liu, M. , Hsieh, Y. , Li, T. , Wu, T. and Chen, C. (2014) Immunological Responses against Different Lineages of Influenza B Antigen in School Children during Two Consecutive Seasons. Health, 6, 2837-2847. doi: 10.4236/health.2014.621322.