Translator Disclaimer
5 November 2020 Identification of Efficacious Vaccines Against Contemporary North American H7 Avian Influenza Viruses
Erica Spackman, Mary J. Pantin-Jackwood, Ioannis Sitaras, Christopher B. Stephens, David L. Suarez
Author Affiliations +
Abstract

Five vaccines, including four inactivated, whole-virus water-in-oil adjuvanted vaccines and a commercial nonreplicating alphavirus-vectored RNA particle (RP) vaccine were evaluated in chickens for their ability to provide protection against challenge with a recent H7 highly pathogenic avian influenza virus (AIV) from the United States (A/turkey/IN/1403-1/2016 H7N8). One of the inactivated vaccines and the RP vaccine were prepared with A/turkey/IN/16-01571-6/2016 H7N8 low pathogenic AIV (LPAIV; TK/IN/16), which is identical to the challenge virus, except for the proteolytic cleavage site of the hemagglutinin protein. The remaining three inactivated vaccines were prepared with other North American H7 LPAIVs. The hemagglutination inhibition assay was used to evaluate the antigenic relationships among the vaccines and selected recent H7 AIV isolates. All five vaccines provided protection against mortality. The inactivated vaccines reduced virus shedding significantly at 2 and 4 days post challenge compared with sham-vaccinated chickens. In contrast, the RP vaccine did not significantly reduce virus shedding. The inactivated vaccine prepared with TK/IN/16 elicited the highest antibody responses, which suggests it is a strong candidate for use as an antigen for North American H7 AIVs. Antigenic distance calculations showed that the four inactivated vaccine strains and other recent North American H7 isolates are antigenically similar, which suggests that the vaccines evaluated here would be similar enough to provide protection to other North American H7 AIVs. If future H7 outbreaks in poultry warrant vaccination, the field strain can be rapidly evaluated with these antigens and, if adequately related, one of these characterized strains may be used.

Erica Spackman, Mary J. Pantin-Jackwood, Ioannis Sitaras, Christopher B. Stephens, and David L. Suarez "Identification of Efficacious Vaccines Against Contemporary North American H7 Avian Influenza Viruses," Avian Diseases 65(1), 113-121, (5 November 2020). https://doi.org/10.1637/aviandiseases-D-20-00109
Received: 1 October 2020; Accepted: 5 November 2020; Published: 5 November 2020
JOURNAL ARTICLE
9 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top