Duration of protection and humoral immunity induced by an adenovirus-vectored subunit vaccine for foot-and-mouth disease (FMD) in Holstein steers

Authors: SITT, TATJANA - University Of Vermont; KEENEY, MARY - Former ARS Employee; BARRERA, JOSE - Leidos; PANDYA, MITAL - University Of Vermont; ECKSTROM, KORIN - University Of Vermont; WARNER, MEGAN - Former ARS Employee; PACHECO, JUAN - Former ARS Employee; LAROCCO, MICHAEL - Former ARS Employee; PALAREA-ALBALADEJO, JAVIER - Biomathematics And Statistics Scotland (BIOSS); BRAKE, DAVID - Bioquest Associates, Llc; Rieder, Aida - Elizabeth; Arzt, Jonathan; BARLOW, JOHN - University Of Vermont; GOLDE, WILLIAM - Former ARS Employee

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 8/13/2019
Publication Date: 9/5/2019
Citation: Sitt, T., Keeney, M., Barrera, J., Pandya, M., Eckstrom, K., Warner, M., Pacheco, J., Larocco, M., Palarea-Albaladejo, J., Brake, D., Rieder, A.E., Arzt, J., Barlow, J., Golde, W. 2019. Duration of protection and humoral immunity induced by an adenovirus-vectored subunit vaccine for foot-and-mouth disease (FMD) in Holstein steers. Meeting Abstract. https://doi.org/10.1016/j.vaccine.2019.08.017.
DOI: https://doi.org/10.1016/j.vaccine.2019.08.017

Interpretive Summary:

Technical Abstract: Foot-and-mouth disease (FMD) is caused by an Aphtovirus in the Picornaviridae Family, affecting cloven-hooved animals. In endemic countries, FMD causes billions of dollars (USD) in losses per year. To date, vaccination with chemically-inactivated vaccines has been relatively successful in prophylactic disease control and eradication, however, semi-annual vaccine boosts are necessary and costly. An efficacious, long acting vaccine is critical to control FMD. The human replication deficient adenovirus 5 (Ad5) empty capsid FMDV platform (AdtFMD), is a promising new vaccine technology. The first vaccine using the AdtFMD platform (AdtA24) licensed by the USDA, is protective against homologous challenge 7 days post-vaccination, it is safe for manufacture and allows differentiation of infected from vaccinated animals (DIVA). Additionally, this vaccine is non-replication and does not shed the vaccine virus vector. Three studies using AdtA24 vaccine from a pre-licensing serial were conducted to assess the proportion of animals protected from clinical vesicular disease following infectious-FMDV challenge at 6 or 9 months following a single vaccination, and the potential effect of vaccination route (transdermal, intramuscular, subcutaneous) on clinical outcome. Results demonstrated that a single dose AdtA24 vaccination in cattle induced protection against clinical FMD at 6 months (100% transdermal, 80% intramuscular, and 60% subcutaneous) that waned by 9 months post-vaccination (33% transdermal and 20% intramuscular). Animals vaccinated by the transdermal route were 2.7 times more likely to be protected following live virus challenge compared to intramuscular vaccinated steers (p<0.001) and animals vaccinated by the subcutaneous route were 4 and 10 times more likely to have foot lesions post-challenge compared to intramuscular (p<0.001) and transdermal (p<0.001) vaccinated animals, respectively. Day 14 post-vaccination serum from immunized cattle generally contained FMDV specific neutralizing antibodies. These data reveal important performance characteristics of needle-free vaccination with a recombinant vectored FMD subunit vaccine.