Whole-Genome Sequence Analysis of Postpandemic Influenza A(H1N1)pdm09 Virus Isolates from India

Abstract

The pandemic influenza A(H1N1)pdm09 virus was first detected in India in May 2009 and continued to circulate in the postpandemic period. Whole-genome sequence analysis of postpandemic A(H1N1)pdm09 viruses showed the circulation of clade 6 and clade 7 viruses. The hemagglutinin (HA) gene showed increased diversity compared with that in the pandemic phase.

Emergence of influenza A(H1N1)pdm09 genogroup 6B and drug resistant virus, India, January to May 2015

“…A thorough in silico analysis revealed that all of the 11 mutations common to the 2015 Indian sequences studied here, have been reported in different strains of influenza A(H1N1)pdm09 virus isolated from various parts of the world in the past [8][9][10]. However, to date, no single strain was reported to possess all these 11 mutations together, except the Indian 2015 strains sequenced in this study.…”

Full Genome Analysis of Influenza A(H1N1)pdm09 Virus Isolated from Peru, 2013

“…This concern seems relevant because the viral strain utilized for vaccine development (the influenza A/California/7/2009 strain) does not carry the mutant form of the HA protein (5). …”

Similarity of currently circulating H1N1 virus with the 2009 pandemic clone: Viability of an imminent pandemic

“…The epidemiology of H1N1pdm09 virus in the United Kingdom during 2009-2011 was characterized by 3 distinct waves: first wave, April-August 2009; second wave, September 2009-April 2010; and third wave, August 2010-April 2011 (Sridhar et al, 2013). In the post pandemic period, the virus remained in circulation and showed unusually increased activity and severity in March and April, for three consecutive years, which is certainly unseasonal (Dakhave et al, 2013). Since November 2013, the Public Health Agency of Canada has received a number of reports of illness caused by the influenza A H1N1 flu virus among young and middle-aged adults (http://www.phac-aspc.gc.…”