Objectives: In the post-pandemic period 2010-2015, seasonal influenza A(H3N2) virus predominated in Hangzhou, southeast of China, with an increased activity and semi-annual seasons. This study utilized HA virus gene segment sequences to analyze the divergence date and vaccine strain match of human influenza A(H3N2) virus from systematic influenza surveillance in Hangzhou.
Methods: Virological and serological analyses of 124 representative A(H3N2) viruses from prospective studies of systematic surveillance samples were conducted to quantify the genetic and antigenic characteristics and their vaccine strain match.
Results: Bayesian phylogenetic inference showed that two separate subgroups 3C.3 and 3C.2 probably diverged from group 3C in early 2012 and then evolved into groups 3C.3a and 3C.2a, respectively, in the 2014/15 influenza season. Furthermore, high amino acid substitution rates of the HA1 subunit were found in A(H3N2) group 3C.2a variants, indicating that increased antigenic drift of A(H3N2) group 3C.2a virus is associated with a vaccine mismatch to the 2015/16 vaccine reference strain Switzerland/9715293/2013 (group 3C.3a).
Conclusions: A portion of the group 3C.2a isolates are not covered by the current A(H3N2) vaccine strain. These findings offer insights into the emergence of group 3C.2a variants with epidemic potential in the imminent influenza seasons.
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http://dx.doi.org/10.1016/j.ijid.2015.09.013 | DOI Listing |
Vet Res Commun
January 2025
College of Animal Science and Veterinary Medicine, Tianjin Agricultural University, No.22, Jinjing Road, Xiqing District, Tianjin, 300384, China.
Recent outbreaks of PRRSV in live attenuated vaccine-immunized pig farms in Tianjin, China have raised questions about the etiological characteristics and pathogenicity of the PRRSV variant, which remains unknown. In this study, a multiple lineages recombinant PRRSV strain named TJ-C6, was isolated and identified. Phylogenetic trees and genome homology analyses revealed that TJ-C6 belonged to lineage 1.
View Article and Find Full Text PDFJ Virol
January 2025
MRC Translational Immune Discovery Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom.
Unlabelled: Current influenza vaccination approaches protect against specific viral strains, but do not consistently induce broad and long-lasting protection to the diversity of circulating influenza viruses. Single-cycle viruses delivered to the respiratory tract may offer a promising solution as they safely express a diverse array of viral antigens by undergoing just one round of cell infection in their host and stimulate broadly protective resident memory T-cell responses in the lung. We have previously developed a vaccine candidate called S-FLU, which is limited to a single cycle of infection by inactivation of the hemagglutinin signal sequence and induces a broadly cross-reactive T-cell response and antibodies to neuraminidase, but fails to induce neutralizing antibodies to hemagglutinin after intranasal administration.
View Article and Find Full Text PDFJ Med Virol
February 2025
Key Laboratory of Artificial Organs and Computational Medicine in Zhejiang Province, Shulan International Medical College, Zhejiang Shuren University, Hangzhou, Zhejiang, P. R. China.
Immunity against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can be induced through either infection with the virus or vaccination, providing protection against reinfection or reducing the risk of severe clinical outcomes. In this study, we recruited 172 volunteers who received different vaccination regimens, including 124 individuals who had recovered from breakthrough infections caused by the Omicron variant (27 with 2 doses, 49 with 3 doses, and 48 with 4 doses) and 48 healthy donors who did not experience breakthrough infections (all of whom received a fourth dose during the infection wave). We measured neutralizing antibody levels against Omicron BA.
View Article and Find Full Text PDFHum Vaccin Immunother
December 2025
Crucell Integration, Janssen Research and Development, Beerse, Belgium.
We conducted a randomized, Phase 2 trial to assess the safety and humoral immunogenicity of reduced doses/dose volume of the standard dose of Ad26.COV2.S COVID-19 vaccine (5 × 10 viral particles [vp]) in healthy adolescents aged 12-17 years.
View Article and Find Full Text PDFUnlabelled: Caliciviruses are significant agricultural and human pathogens that are poorly understood due to the dearth of molecular tools, including reporter systems. We report the development of a stable, faithful, and robust luciferase-based reporter system for a model calicivirus, murine norovirus (MNoV). Genetic insertion of a HiBiT tag, an 11 amino acid fragment of nanolucifersase, at the junction of the nonstructural proteins NS4 and NS5 yields infectious virus.
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