Abstract
Influenza viruses are by nature unstable with high levels of mutations. The sequential accumulation of mutations in the surface glycoproteins allows the virus to evade the neutralizing antibodies. The consideration of the tropics as the influenza reservoir where viral genetic and antigenic diversity are continually generated and reintroduced into temperate countries makes the study of influenza virus evolution in Indonesia essential. A total of 100 complete coding sequences (CDS) of Hemagglutinin (HA) and Neuraminidase (NA) genes of H3N2 virus were obtained from archived samples of Influenza-Like Illness (ILI) surveillance collected from 2008 to 2010. Our evolutionary and phylogenetic analyses provide insight into the dynamic changes of Indonesian H3N2 virus from 2008 to 2010. Obvious antigenic drift with typical ‘ladder-like’ phylogeny was observed with multiple lineages found in each year, suggesting co-circulation of H3N2 strains at different time periods. The mutational pattern of the Indonesian H3N2 virus was not geographically related as relatively low levels of mutations with similar pattern of relative genetic diversity were observed in various geographical origins. This study reaffirms that the existence of a particular lineage is most likely the result of adaptation or competitive exclusion among different host populations and combination of stochastic ecological factors, rather than its geographical origin alone.
Highlights
Influenza A viruses cause acute respiratory disease in humans and are responsible for annual epidemic with 3–5 million hospitalization and approximately 500,000 deaths globally [1]
The present study describes the evolutionary analyses of HA and NA genes of Influenza A/H3N2 virus in Indonesia from 2008 to 2010
The study samples were 242 archived clinical specimens of nasal swabs with confirmed H3N2-positivity obtained during the Influenza-Like Illness (ILI) Surveillance, which was conducted by the National Institute of Health Research and Development (NIHRD), Indonesia, from 2008 to 2010
Summary
Influenza A viruses cause acute respiratory disease in humans and are responsible for annual epidemic with 3–5 million hospitalization and approximately 500,000 deaths globally [1]. Influenza viruses activities typically occur in the winter season, characterized by the increasing number of influenza cases and associated deaths above a seasonal baseline, known as seasonal influenza pandemic [2]. In the tropics, influenza occurs throughout the year without a well-defined pattern, there is some evidence of higher frequency of respiratory viral infections in rainy season [3].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
