Full genomic analysis of an influenza A (H1N2) virus identified during 2009 pandemic in Eastern India: evidence of reassortment event between co-circulating A(H1N1)pdm09 and A/Brisbane/10/2007-like H3N2 strains.
BACKGROUND
During the pandemic [Influenza A(H1N1)pdm09] period in 2009-2010, an influenza A (Inf-A) virus with H1N2 subtype (designated as A/Eastern India/N-1289/2009) was detected from a 25 years old male from Mizoram (North-eastern India).


OBJECTIVE
To characterize full genome of the H1N2 influenza virus.


METHODS
For initial detection of Influenza viruses, amplification of matrix protein (M) gene of Inf-A and B viruses was carried out by real time RT-PCR. Influenza A positive viruses are then further subtyped with HA and NA gene specific primers. Sequencing and the phylogenetic analysis was performed for the H1N2 strain to understand its origin.


RESULTS
The outcome of this full genome study revealed a unique reassortment event where the N-1289 virus acquired it's HA gene from a 2009 pandemic H1N1 virus with swine origin and the other genes from H3N2-like viruses of human origin.


CONCLUSIONS
This study provides information on possibility of occurrence of reassortment events during influenza season when infectivity is high and two different subtypes of Inf-A viruses co-circulate in same geographical location.
National Institute of Cholera and Enteric Diseases, Beliaghata, Kolkata, India.
Tapasi Roy
TR
Mukherjee
Anurodh S
AS
Agrawal
Sekhar
S
Chakrabarti
Mamta
M
Chawla-Sarkar
D000328:Adult; D016000:Cluster Analysis; D016679:Genome, Viral; D006801:Humans; D007194:India / Q000453:epidemiology; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics*; D057221:Influenza A Virus, H1N2 Subtype / Q000235:genetics* / Q000302:isolation & purification*; D053122:Influenza A Virus, H3N2 Subtype / Q000235:genetics*; D007251:Influenza, Human / Q000453:epidemiology / Q000821:virology*; D008297:Male; D008969:Molecular Sequence Data; D058873:Pandemics; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D016865:Reassortant Viruses / Q000235:genetics* / Q000302:isolation & purification*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
D012367:RNA, Viral