RESUMO
The WHO Global Influenza Surveillance Network has routinely performed genetic and antigenic analyses of human influenza viruses to monitor influenza activity. Although these analyses provide supporting data for the selection of vaccine strains, it seems desirable to have user-friendly tools to visualize the antigenic evolution of influenza viruses for the purpose of surveillance. To meet this need, we have developed a web server, ATIVS (Analytical Tool for Influenza Virus Surveillance), for analyzing serological data of all influenza viruses and hemagglutinin sequence data of human influenza A/H3N2 viruses so as to generate antigenic maps for influenza surveillance and vaccine strain selection. Functionalities are described and examples are provided to illustrate its usefulness and performance. The ATIVS web server is available at http://influenza.nhri.org.tw/ATIVS/.
Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Orthomyxoviridae/imunologia , Software , Variação Antigênica , Antígenos Virais/química , Antígenos Virais/genética , Gráficos por Computador , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Influenza Humana/epidemiologia , Orthomyxoviridae/classificação , Vigilância da População , Análise de SequênciaRESUMO
MOTIVATION: Continual and accumulated mutations in hemagglutinin (HA) protein of influenza A virus generate novel antigenic strains that cause annual epidemics. RESULTS: We propose a model by incorporating scoring and regression methods to predict antigenic variants. Based on collected sequences of influenza A/H3N2 viruses isolated between 1971 and 2002, our model can be used to accurately predict the antigenic variants in 1999-2004 (agreement rate = 91.67%). Twenty amino acid positions identified in our model contribute significantly to antigenic difference and are potential immunodominant positions.
