tetano
Editor, Senior Moderator
Infect Genet Evol. 2020 Feb 24:104264. doi: 10.1016/j.meegid.2020.104264. [Epub ahead of print] [h=1]Evolutionary dynamics of influenza B strains detected from paediatric acute respiratory infections in central Vietnam.[/h]
Yoshihara K[SUP]1[/SUP], Minh LN[SUP]2[/SUP], Okada T[SUP]1[/SUP], Toizumi M[SUP]1[/SUP], Nguyen HA[SUP]2[/SUP], Vo HM[SUP]3[/SUP], Hashizume M[SUP]1[/SUP], Dang DA[SUP]2[/SUP], Kimura H[SUP]4[/SUP], Yoshida LM[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza virus B belongs to the family Orthomyxoviridae with segmented negative-sense RNA genomes. Since 1970s, influenza B has diverged intoVictoria and Yamagata, which differs in antigenic and evolutionary characteristics. Yet, molecular-epidemiological information of influenza B from developing nations is limited. In central Vietnam, influenza A subtype-specific circulation pattern and clinical characteristics were previously described. However, molecular evolutionary characteristics of influenza B has not been discussed to date. We utilized the influenza B positives obtained from paediatric ARI surveillance during 2007-2013. Influenza B HA and NA genes were amplified, sequenced, and phylogenetic/molecular evolutionary analysis was performed using Maximum Likelihood and Bayesian MCMC. Phylodynamics analysis was performed with Bayesian Skyline Plot (BSP). Furthermore, we performed selection pressure analysis and estimated N-glycosylation sites. In the current study, overall positive rate for influenza B was 3.0%, and Victoria lineage immediately became predominant in post-A/H1N1pdm09 period. The noticeable shift in Victoria lineage WHO Group occurred. With respect to the evolutionary rate (substitutions/site/year), Victoria lineage HA gene was evolving faster than Yamagata lineage (2.43 ? 10[SUP]-3[/SUP] vs 2.00 ? 10[SUP]-3[/SUP]). Furthermore, the evolutionary rate of Victoria Group 5 was greater than Group 1. BSP presented the rapid growth in Effective Population Size (EPS) of Victoria lineage occurred soon after the 1st A/H1N1pdm09 case was detected whereas the EPS of Yamagata lineage was stable for both genes. N-glycosylation pattern between lineages and among WHO Groups were slightly different, and HA gene had a total of 6 amino acid substitutions under positive section pressure (4 for Victoria and 2 for Yamagata). The current results highlight the importance of Victoria lineage in post-A/H1N1pdm09 period. Difference in evolutionary characteristics and phylodynamics may indicate lineage and WHO Group-specific evolutionary dynamics. It is necessary to further continue the molecular-epidemiological surveillance in local setting to gain a better understanding of local evolutionary characteristics of influenza B strains.
Copyright ? 2019. Published by Elsevier B.V.
[h=4]KEYWORDS:[/h] ARI; Influenza B; Molecular evolution; Paediatric infectious disease; Phylogenetic; Vietnam
PMID: 32105864 DOI: 10.1016/j.meegid.2020.104264
Yoshihara K[SUP]1[/SUP], Minh LN[SUP]2[/SUP], Okada T[SUP]1[/SUP], Toizumi M[SUP]1[/SUP], Nguyen HA[SUP]2[/SUP], Vo HM[SUP]3[/SUP], Hashizume M[SUP]1[/SUP], Dang DA[SUP]2[/SUP], Kimura H[SUP]4[/SUP], Yoshida LM[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza virus B belongs to the family Orthomyxoviridae with segmented negative-sense RNA genomes. Since 1970s, influenza B has diverged intoVictoria and Yamagata, which differs in antigenic and evolutionary characteristics. Yet, molecular-epidemiological information of influenza B from developing nations is limited. In central Vietnam, influenza A subtype-specific circulation pattern and clinical characteristics were previously described. However, molecular evolutionary characteristics of influenza B has not been discussed to date. We utilized the influenza B positives obtained from paediatric ARI surveillance during 2007-2013. Influenza B HA and NA genes were amplified, sequenced, and phylogenetic/molecular evolutionary analysis was performed using Maximum Likelihood and Bayesian MCMC. Phylodynamics analysis was performed with Bayesian Skyline Plot (BSP). Furthermore, we performed selection pressure analysis and estimated N-glycosylation sites. In the current study, overall positive rate for influenza B was 3.0%, and Victoria lineage immediately became predominant in post-A/H1N1pdm09 period. The noticeable shift in Victoria lineage WHO Group occurred. With respect to the evolutionary rate (substitutions/site/year), Victoria lineage HA gene was evolving faster than Yamagata lineage (2.43 ? 10[SUP]-3[/SUP] vs 2.00 ? 10[SUP]-3[/SUP]). Furthermore, the evolutionary rate of Victoria Group 5 was greater than Group 1. BSP presented the rapid growth in Effective Population Size (EPS) of Victoria lineage occurred soon after the 1st A/H1N1pdm09 case was detected whereas the EPS of Yamagata lineage was stable for both genes. N-glycosylation pattern between lineages and among WHO Groups were slightly different, and HA gene had a total of 6 amino acid substitutions under positive section pressure (4 for Victoria and 2 for Yamagata). The current results highlight the importance of Victoria lineage in post-A/H1N1pdm09 period. Difference in evolutionary characteristics and phylodynamics may indicate lineage and WHO Group-specific evolutionary dynamics. It is necessary to further continue the molecular-epidemiological surveillance in local setting to gain a better understanding of local evolutionary characteristics of influenza B strains.
Copyright ? 2019. Published by Elsevier B.V.
[h=4]KEYWORDS:[/h] ARI; Influenza B; Molecular evolution; Paediatric infectious disease; Phylogenetic; Vietnam
PMID: 32105864 DOI: 10.1016/j.meegid.2020.104264