tetano
Editor, Senior Moderator
Sci Rep. 2017 May 2;7(1):1323. doi: 10.1038/s41598-017-01512-x.
[h=1]A reassortant H9N2 influenza virus containing 2009 pandemic H1N1 internal-protein genes acquired enhanced pig-to-pig transmission after serial passages in swine.[/h] Mancera Gracia JC[SUP]1[/SUP], Van den Hoecke S[SUP]2,[/SUP][SUP]3[/SUP], Richt JA[SUP]4[/SUP], Ma W[SUP]4[/SUP], Saelens X[SUP]2,[/SUP][SUP]3[/SUP], Van Reeth K[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Avian H9N2 and 2009 pandemic H1N1 (pH1N1) influenza viruses can infect pigs and humans, raising the concern that H9N2
H1N1 reassortant viruses could emerge. Such reassortants demonstrated increased replication and transmissibility in pig, but were still inefficient when compared to pH1N1. Here, we evaluated if a reassortant virus containing the hemagglutinin and neuraminidase of A/quail/Hong Kong/G1/1997 (H9N2) in the A/California/04/2009 (pH1N1) backbone could become better adapted to pigs by serial passaging. The tropism of the original H9N2H1N1 (P0) virus was restricted to the nasal mucosa, with no virus detected in the trachea or lungs. Nevertheless, after seven passages the H9N2H1N1 (P7) virus replicated in the entire respiratory tract. We also compared the transmissibility of H9N2H1N1 (P0), H9N2H1N1 (P7) and pH1N1. While only 2/6 direct-contact pigs showed nasal virus excretion of H9N2H1N1 (P0) ≥five days, 4/6 direct-contact animals shed the H9N2H1N1 (P7). Interestingly, those four animals shed virus with titers similar to those of the pH1N1, which readily transmitted to all six contact animals. The broader tissue tropism and the increased post-transmission replication after seven passages were associated with the HA-D225G substitution. Our data demonstrate that the pH1N1 internal-protein genes together with the serial passages favour H9N2 virus adaptation to pigs.
PMID: 28465552 DOI: 10.1038/s41598-017-01512-x
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[h=1]A reassortant H9N2 influenza virus containing 2009 pandemic H1N1 internal-protein genes acquired enhanced pig-to-pig transmission after serial passages in swine.[/h] Mancera Gracia JC[SUP]1[/SUP], Van den Hoecke S[SUP]2,[/SUP][SUP]3[/SUP], Richt JA[SUP]4[/SUP], Ma W[SUP]4[/SUP], Saelens X[SUP]2,[/SUP][SUP]3[/SUP], Van Reeth K[SUP]5[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Avian H9N2 and 2009 pandemic H1N1 (pH1N1) influenza viruses can infect pigs and humans, raising the concern that H9N2
H1N1 reassortant viruses could emerge. Such reassortants demonstrated increased replication and transmissibility in pig, but were still inefficient when compared to pH1N1. Here, we evaluated if a reassortant virus containing the hemagglutinin and neuraminidase of A/quail/Hong Kong/G1/1997 (H9N2) in the A/California/04/2009 (pH1N1) backbone could become better adapted to pigs by serial passaging. The tropism of the original H9N2H1N1 (P0) virus was restricted to the nasal mucosa, with no virus detected in the trachea or lungs. Nevertheless, after seven passages the H9N2H1N1 (P7) virus replicated in the entire respiratory tract. We also compared the transmissibility of H9N2H1N1 (P0), H9N2H1N1 (P7) and pH1N1. While only 2/6 direct-contact pigs showed nasal virus excretion of H9N2H1N1 (P0) ≥five days, 4/6 direct-contact animals shed the H9N2H1N1 (P7). Interestingly, those four animals shed virus with titers similar to those of the pH1N1, which readily transmitted to all six contact animals. The broader tissue tropism and the increased post-transmission replication after seven passages were associated with the HA-D225G substitution. Our data demonstrate that the pH1N1 internal-protein genes together with the serial passages favour H9N2 virus adaptation to pigs.PMID: 28465552 DOI: 10.1038/s41598-017-01512-x
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