Molecular characterization of influenza A(H1N1)pdm09 viruses circulating at various geographical locations in India, 2017

Abstract

Background & objectives:Influenza virological surveillance is an essential tool for the early detection of novel genetic variants of epidemiologic and clinical significance. This study was aimed to genetically characterize A(H1N1)pdm09 virus circulating in 2017 and to compare it with the global data.Methods:The regional/State Viral Research and Diagnostic Laboratories (VRDLs) provided influenza diagnosis for referred clinical samples and shared influenza A(H1N1)pdm09 positives with the Indian Council of Medical Research-National Institute of Virology (ICMR-NIV), Pune, India, for hemagglutinin (HA) gene phylogenetic analysis. Sites at Manipal, Jaipur and Dibrugarh performed the sequencing and shared the sequence data for analysis. The antiviral susceptibility of influenza viruses was assessed for known molecular marker H275Y at the ICMR-NIV, Pune.Results:All the eight VRDLs had well-established influenza diagnostic facilities and showed increased activity of influenza A(H1N1)pdm09 during 2017. Phylogenetic analysis showed that the viruses from the different regions of the country were similar to A/Michigan/45/2015 strain which was the 2017-2018 recommended vaccine strain and were clustered with the globally circulating clade 6B.1 with signature mutations S84N, S162N and I216T. The clade 6B.1 showed further subgrouping with additional mutations S74R, S164T and I295V; however, there was no significant association between the presence of these mutations and severity of disease due to influenza. All the study viruses were sensitive to oseltamivir.Interpretation & conclusions:During the study period, all the study sites reported globally circulating A/Michigan/45/2015 vaccine strain of influenza A(H1N1)pdm09 viruses and remained sensitive to oseltamivir. Further genetic and antigenic characterization of influenza viruses is recommended to address public health concerns.

Sequence-Based Antigenic Analyses of H1 Swine Influenza A Viruses from Colombia (2008–2021) Reveals Temporal and Geographical Antigenic Variations

“…The origin of this pattern could be related to the independent introduction of two genetically related FLUAV into pigs from different geographic sources during the international movement of animals and humans. It is probable that Colombian viruses from this cluster originated from a global human FLUAV, considering the presence of mutations K163G, E235D, and S74R, and the gain of an N-Glycosylation motif at 162 previously reported in pandemic viruses from humans [ 54 , 55 , 56 , 57 ]. The cluster likely reached swine populations in Eurasia and North America, from where it was then introduced to Colombia.…”

Respiratory Viruses Among Ethnic Nicobarese During COVID-19 Pandemic

“…Keeping in view of history of in uenza H1N1 pandemic the surveillance activities were strengthened in Car Nicobar [15]. The rst incidence of COVID-19 infection reported in Kerala on January 31, 2020 [16].…”