tetano
Editor, Senior Moderator
J Virol. 2018 Sep 5. pii: JVI.01323-18. doi: 10.1128/JVI.01323-18. [Epub ahead of print]
[h=1]Comparison of adjuvanted-whole inactivated virus and live-attenuated virus vaccines against challenge with contemporary, antigenically distinct swine H3N2 influenza A viruses.[/h] Abente EJ[SUP]1[/SUP], Rajao DS[SUP]1[/SUP], Santos J[SUP]2[/SUP], Kaplan BS[SUP]1[/SUP], Nicholson TL[SUP]1[/SUP], Brockmeier SL[SUP]1[/SUP], Gauger PC[SUP]3[/SUP], Perez DR[SUP]2[/SUP], Vincent AL[SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza A virus in swine (IAV-S) circulating in the United States of America are phylogenetically and antigenically distinct. A human H3 hemagglutinin (HA) was introduced in the IAV-S gene pool in the late 1990s, sustained continued circulation, and evolved into five monophyletic genetic clades after 2009, H3 IVA-E. Across these phylogenetic clades, distinct antigenic clusters were identified, with three clusters (cyan, red and green) among the most frequently detected antigenic phenotypes. Although it was demonstrated that antigenic diversity of H3N2 IAV-S was associated with changes at a few amino acid positions in the head of the HA, the implications of this diversity on vaccine efficacy was not tested. Using antigenically representative H3N2 viruses, we compared whole inactivated virus (WIV) and live attenuated influenza vaccine (LAIV) vaccines for protection against challenge with antigenically distinct H3N2 viruses in pigs. WIV provided partial protection against antigenically distinct viruses, but did not prevent virus replication in the upper respiratory tract. In contrast, LAIV provided complete protection from disease and virus was not detected after challenge with antigenically distinct viruses.IMPORTANCE Due to the rapid evolution of the influenza A virus, vaccines require continuous strain updates. Additionally, the platform used to deliver the vaccine can have an impact on the breadth of protection. Currently, there are various vaccine platforms available to prevent influenza A virus infection in swine, and we experimentally tested two: adjuvanted-whole inactivated virus and live attenuated virus. When challenged with an antigenically distinct virus, adjuvanted-whole inactivated virus provided partial protection while live attenuated virus provided effective protection. Additional strategies are required to broaden the protective properties of inactivated virus vaccines given the dynamic antigenic landscape of co-circulating strains in North America, whereas live attenuated vaccines may require less frequent strain updates based on demonstrated cross-protection. Enhancing vaccine efficacy to control influenza infections in swine will help reduce the impact it has on swine production and reduce the risk of swine-to-human transmission.
PMID: 30185589 DOI: 10.1128/JVI.01323-18
Free full text
[h=1]Comparison of adjuvanted-whole inactivated virus and live-attenuated virus vaccines against challenge with contemporary, antigenically distinct swine H3N2 influenza A viruses.[/h] Abente EJ[SUP]1[/SUP], Rajao DS[SUP]1[/SUP], Santos J[SUP]2[/SUP], Kaplan BS[SUP]1[/SUP], Nicholson TL[SUP]1[/SUP], Brockmeier SL[SUP]1[/SUP], Gauger PC[SUP]3[/SUP], Perez DR[SUP]2[/SUP], Vincent AL[SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza A virus in swine (IAV-S) circulating in the United States of America are phylogenetically and antigenically distinct. A human H3 hemagglutinin (HA) was introduced in the IAV-S gene pool in the late 1990s, sustained continued circulation, and evolved into five monophyletic genetic clades after 2009, H3 IVA-E. Across these phylogenetic clades, distinct antigenic clusters were identified, with three clusters (cyan, red and green) among the most frequently detected antigenic phenotypes. Although it was demonstrated that antigenic diversity of H3N2 IAV-S was associated with changes at a few amino acid positions in the head of the HA, the implications of this diversity on vaccine efficacy was not tested. Using antigenically representative H3N2 viruses, we compared whole inactivated virus (WIV) and live attenuated influenza vaccine (LAIV) vaccines for protection against challenge with antigenically distinct H3N2 viruses in pigs. WIV provided partial protection against antigenically distinct viruses, but did not prevent virus replication in the upper respiratory tract. In contrast, LAIV provided complete protection from disease and virus was not detected after challenge with antigenically distinct viruses.IMPORTANCE Due to the rapid evolution of the influenza A virus, vaccines require continuous strain updates. Additionally, the platform used to deliver the vaccine can have an impact on the breadth of protection. Currently, there are various vaccine platforms available to prevent influenza A virus infection in swine, and we experimentally tested two: adjuvanted-whole inactivated virus and live attenuated virus. When challenged with an antigenically distinct virus, adjuvanted-whole inactivated virus provided partial protection while live attenuated virus provided effective protection. Additional strategies are required to broaden the protective properties of inactivated virus vaccines given the dynamic antigenic landscape of co-circulating strains in North America, whereas live attenuated vaccines may require less frequent strain updates based on demonstrated cross-protection. Enhancing vaccine efficacy to control influenza infections in swine will help reduce the impact it has on swine production and reduce the risk of swine-to-human transmission.
PMID: 30185589 DOI: 10.1128/JVI.01323-18
Free full text