Abstract
Influenza A virus is the most unpredictable global threat, past pandemic witnessed the community swaps happened due to this virus. The recent emergence of H7N9 in China is the result of new and recent reassortmant of Influenza A virus. Emergence of a novel human influenza A virus (H1N1pdm) in 2009 is an unprecedent event of molecular virology. This novel emerged virus affected millions of persons and raised WHO pandemic alert to phase 6. Therefore continuous monitoring is required to have adequate genome information and to track mutations during course of viral evolution. In present study we investigated acute phase suspected H1N1pdm clinical samples from North India 2012-2013. H1N1pdm virus confirmed positive samples were proceeded for virus isolation in MDCK cells. Complete HA gene was deciphered and phylogenetic analysis of Indian H1N1pdm virus isolate was carried out with respect to globally diversified H1N1pdm virus. CDC Real time RT-PCR revealed 15% positivity for H1N1pdm virus. Complete HA gene sequence characterization of Indian H1N1pdm 2012-2013 virus and their phylogenetic analysis with respect to circulating global viruses revealed continuous circulation of cosmopolitan Clade VII in India. In the course of its evolution, 2009-2013 the virus acquired many mutations and which could be responsible for severity of this virus and emergence of new virus subtypes. India also witnessed high morbidity and mortality reported from all parts of the country. This study clearly indicates that recently reported cosmopolitan clade VII has undergone positive selection in India as well globally revealed continuous circulation of clade VII since 2009. This study of recent H1N1pdm Indian virus isolate will facilitate future epidemiological surveillance in Indian subcontinent and abroad.
Highlights
The 2009 Swine Flu pandemic is caused by a novel reasserted H1N1 subtype of H1N1 influenza A virus that had not been recognized previously in swine or humans
The largest proportion of genes comes from swine influenza viruses (30.6% from North American swine influenza strains, 17.5% from Eurasian swine influenza strains), followed by North American avian influenza strains (34.4%) and human influenza strains (17.5%)
Throat/Nasal) samples suspected for H1N1pdm virus, from the patients having history of suspected Influenza A like illness were referred from sentinel hospitals in Gwalior, India
Summary
The 2009 Swine Flu pandemic is caused by a novel reasserted H1N1 subtype of H1N1 influenza A virus that had not been recognized previously in swine or humans. This newly emerged strain represents a quadruple reassortment of two swine strains, one human strain, and one avian strain of influenza. The HA protein is critical for binding to cellular receptors and fusion of the viral and endosomal membranes [2] Several reports described both emergence and pandemic potential of the virus in the perspective of earlier pandemic influenza viruses of 1918 (H1N1), 1957 (H2N2) and 1968 (H3N2) through comparison of the available genetic sequence data [3]. World Health Organization declared the outbreak a global pandemic in June 2009 [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callMore From: Journal of Phylogenetics & Evolutionary Biology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
