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SARS-CoV-2, a positive-strand RNA virus, utilizes both genomic replication and subgenomic mRNA transcription. Whole genome sequencing (WGS) from clinical samples can estimate viral gene expression levels. WGS was conducted on 529 SARS-CoV-2 positive clinical samples from Assam and northeastern India to track viral emergence and assess gene expression patterns. The results reveal differential expression across structural, non-structural, and accessory genes, with notable upregulation of the M gene, especially in the Omicron variant, followed by E and ORF6. The mean transcript per million (TPM) expression levels of the M gene were significantly higher in Omicron variants (175 611 ± 46 921), peaking in the KP.1/KP.2 sublineage (220 493 ± 34 917), compared to the Delta variant (129 717 ± 33 773). The relative fold change of M gene expression between Delta and Omicron 2024 subvariants showed a 1.6-fold change. Variant-wise gene expression analysis suggests a correlation between gene expression and viral mutation, impacting replication. As anticipated, the expression levels of genes surge with the increase in the virus mutation. The Chi-square trend for average substitution count versus average TPM of the M gene was highly significant (72.78., p < 0.0001). The M gene's high expression and low mutation rate make it an ideal target for designing a real-time RT-PCR kit assay. These findings highlight the need for continuous surveillance and understanding of viral gene expression dynamics for effective COVID-19 management. Further studies are necessary to elucidate the significance of these observations in viral pathogenesis and transmission dynamics., (© 2024 Wiley Periodicals LLC.)

Human leucocyte antigen (HLA) represents one of the most highly polymorphic systems which plays a central role in the immune response. Genetic polymorphism of HLA in influenza A(H1N1)pdm09 infected population may be an important factor in disease progression and severity that needs further probing. In this study, a total of 110 Influenza like illness patients were recruited from the population of Assam, Northeast India, from which 35 cases infected by A(H1N1)pdm09 viruses and 35 controls were typed for HLA-A, B and DRB1 locus by PCR-SSP method. A total of seven alleles of HLA-A, 16 alleles of HLA-B, and 11 alleles of HLA-DRB1 locus were identified. The most common alleles within each locus in cases were HLA-A*11 (85.71%, P = 0.046), HLA-B*35 (25%, P = 0.0001), and HLA-DRB1*15 (49.35%,  P = 0.133) as compared to the controls, HLA-A*11 (40.82%), HLA-B*35 (0.00%), and HLA-DRB1*15 (67.53%). The frequency of HLA-A*11 and HLA-B*35 were significantly higher in cases as compared to the controls. In DRB1 locus, HLA-DRB1*10 was significantly higher in cases (20.78%, P = 0.005) than that of controls (0.00%). Whereas, HLA-DRB1*15 showed a higher frequency in controls than in cases. In addition, HLA-DRB3*01 (P = 0.053), DRB4*01 (P = 1.000), and DRB5*01(P = 0.591) were also identified along with HLA-DRB1 haplotype. From this preliminary study, it is suspected that there may be a role of HLA-A*11, HLA-B*35 and HLA-DRB1*10 in conferring susceptibility to influenza A(H1N1)pdm09 infection in the study population. A larger extended study on HLA polymorphism may explain the association between HLA and influenza A(H1N1)pdm09 infection and provide insights for HLA restricted peptide based vaccines., (© 2018 Wiley Periodicals, Inc.)

During August 2013, an outbreak of influenza-like illnesses (ILI) was investigated in Monigong area, near Indo-China border of Arunachal Pradesh, Northeast India. Influenza type A/H3N2 was detected by RT-PCR in 33.3% (8/24) of ILI cases. Sequence analysis of HA and NA genes revealed eight and five amino acid substitutions, respectively in Monigong H3N2 (Mo/H3N2) strains as compared to vaccine strain A/Victoria/361/2011. Four non-synonymous substitutions, three localizing at antigenic sites T144A, A; R158G, B; L173S, D, and one H9Y in close proximity to a potential glycosylation site aa8 in HA1 domain along with the substitution T329N in NA are likely to influence the antigenicity/virulence of Mo/H3N2 viruses. J. Med. Virol. 88:1999-2003, 2016. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

A significant number of children die each year from acute respiratory tract infections especially in developing countries. Human respiratory syncytial virus (RSV) is the most common virus identified in such cases. Genetic characterization and the circulation pattern of RSV is important for future selection of appropriate vaccine strains. Limited information is available on the circulation of RSV in developing countries including India. The present study aimed to provide baseline information on the genetic variability of RSV in the Dibrugarh district of Assam, northeast India. Clinical specimens collected from children aged ≤6 years for routine influenza surveillance in the Dibrugarh district of Assam during the period 2009-2012, were screened for RSV by real-time reverse transcription-polymerase chain reaction. Genotyping was based on partial sequencing of the RSV attachment glycoprotein gene. RSV was detected in 7.9% (39/493) of cases. Only RSV group A viruses were detected during the study period with predominance of NA1 genotypes (89%). Two RSV GA5 genotypes were found to be co-circulating during 2012. The specific amino acid substitutions characteristics of the NA1 genotypes were distinct from RSV strains reported from the rest of India. It is concluded that the circulating genotypes of RSV in Assam, northeast India are NA1 and GA5. To our knowledge this is the first report of circulation of the NA1 genotype in India., (Copyright © 2013 Wiley Periodicals, Inc.)

Simultaneous occurrence of measles and chickenpox in a single individual is a rare event despite the fact that each of these infections alone is very common. The clinical presentation and molecular characterization of a dual infection caused by measles and Varicella-Zoster virus (VZV) in a 3-year female child is reported for the first time from India. The child presented with high fever, cough, cervical lymphadenopathy, and maculopapular rash followed by vesicular skin rash. The child was not immunized against measles and chickenpox. The viral nucleic acids extracted from the clinical specimen were subjected to PCR-Sequencing for confirmation of a dual infection with measles and VZV. The PCR and sequence analysis from the throat swab samples confirmed the coinfection of wild-type measles (genotype D4) and Varicella-Zoster virus (PstI(+) BglI(+)). The measles virus RNA and VZV DNA could be detected successfully from a single specimen of a throat swab. The case recovered uneventfully. Dual infection with measles and VZV does occur but may be underreported in the literature., (Copyright © 2011 Wiley-Liss, Inc.)