ArticleVirus genes2021
Genetic characterisation of the influenza viruses circulating in Bulgaria during the 2019-2020 winter season.
Article in Virus genes, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers.
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11 citing papers in PubMed, 16 citations in OpenAlex.
- Genomic surveillance of H1N1, H3N2 and influenza B Victoria lineage viruses in Qingyang (2020-2023): phylogenetic and molecular characteristics analysis of HA/NA genes.BMC infectious diseases · 2026Article
- H3 hemagglutinin proteins optimized for 2018 to 2022 elicit neutralizing antibodies across panels of modern influenza A(H3N2) viruses.Journal of immunology (Baltimore, Md. : 1950) · 2025Article
- Molecular Evolution of Influenza A Viruses From Mauritius, 2017-2019.Influenza and other respiratory viruses · 2025Article
- Genetic characterization of influenza B virus and oseltamivir resistance in pediatric patients with acute respiratory infections: a cross-sectional study.Virus genes · 2025Article
- Article
- Emergence of Eurasian Avian-Like Swine Influenza A (H1N1) virus in a child in Shandong Province, China.BMC infectious diseases · 2024Article
- mRNA vaccines encoding computationally optimized hemagglutinin elicit protective antibodies against future antigenically drifted H1N1 and H3N2 influenza viruses isolated between 2018-2020.Frontiers in immunology · 2024Article
- Genome characterization of influenza A and B viruses in New South Wales, Australia, in 2019: A retrospective study using high-throughput whole genome sequencing.Influenza and other respiratory viruses · 2024Article
- The genetic diversity, replication, and transmission of 2009 pandemic H1N1 viruses in China.Frontiers in microbiology · 2023Article
- Evolution of Swine Influenza Virus H3N2 in Vaccinated and Nonvaccinated Pigs after Previous Natural H1N1 Infection.Viruses · 2022Article
- Bivalent H1 and H3 COBRA Recombinant Hemagglutinin Vaccines Elicit Seroprotective Antibodies against H1N1 and H3N2 Influenza Viruses from 2009 to 2019.Journal of virology · 2022Article
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5 authors at 1 institution in 1 country.
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Abstract
Influenza viruses have a high potential for genetic changes. The objectives of this study were to analyse influenza virus circulation in Bulgaria during the 2019/2020 season, to perform a phylogenetic and molecular analyses of the haemagglutinin (HA) and neuraminidase (NA) sequences of representative influenza strains, and to identify amino acid substitutions compared to the current vaccine strains. Seasonal influenza viruses A(H3N2), A(H1N1)pdm09 and B/Victoria-lineage were detected using a real-time RT-PCR in 323 (23.3%), 149 (10.7%) and 138 (9.9%) out of 1387 patient samples studied, respectively. The HA genes of A(H3N2) viruses analysed belonged to clades 3C.3a (21 strains) and 3C.2a (5 strains): subclades 3C.2a1b + T131K, 3C.2a1b + T135K-B and 3C.2a1b + T135K-A. The clade 3C.3a and subclade 3C.2a1b viruses carried 5 and 14-17 substitutions in HA, as well as 3 and 9 substitutions in NA, respectively, in comparison with the A/Kansas/14/2017 vaccine virus, including some substitutions in the HA antigenic sites A, B, C and E. All 21 A(H1N1)pdm09 viruses sequenced fell into 6B.1A5A subclade. Amino acid sequence analysis revealed the presence of 7-11 substitutions in HA, compared to the A/Brisbane/02/2018 vaccine virus, three of which occurred in antigenic site Sb, along with 6-9 changes at positions in NA. All 10 B/Victoria-lineage viruses sequenced belonged to clade 1A with a triple deletion in HA1 (genetic group 1A(Δ3)B) and carried 7 and 3 substitutions in HA and NA, respectively, with respect to the B/Colorado/06/2017 vaccine virus. The results of this study confirm the rapid evolution of influenza viruses and the need for continuous antigenic and genetic surveillance.
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