Vaccine-associated enhanced respiratory disease in swine and ferrets

Authors: KIMBLE, J - Oak Ridge Institute For Science And Education (ORISE); BRAND, MEGHAN - Oak Ridge Institute For Science And Education (ORISE); KAPLAN, BRYAN - Oak Ridge Institute For Science And Education (ORISE); ZOUL, JORDYN - Oak Ridge Institute For Science And Education (ORISE); Baker, Amy

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/17/2019
Publication Date: 6/25/2019
Citation: Kimble, J.B., Brand, M.W., Kaplan, B.S., Zoul, J., Vincent, A.L. 2019. Vaccine-associated enhanced respiratory disease in swine and ferrets [abstract]. p. none assigned.

Interpretive Summary:

Technical Abstract: Influenza A virus (IAV) is a major contributor to swine disease in the US and places a substantial burden on the swine industry each year. Genetic diversity is high in US swine herds due to genetic drift and the numerous introductions of human seasonal influenza genes via reverse zoonosis. Whole inactivated vaccines (WIV) are a common control method utilized by the swine industry to control IAV. WIV platforms are effective against antigenically similar viruses. However, enhanced morbidity can happen when the WIV is antigenically mismatched with the infecting virus. Models for vaccine-associated enhanced respiratory disease (VAERD) have been established in swine, but questions remain about its relevance in other species. Here, we attempted to recapitulate VAERD in ferrets, the gold standard animal model for human influenza, in a direct comparison to VAERD in swine. Groups of ferrets and pigs were vaccinated with two doses of whole inactivated dH1N2 SIV in an oil and water adjuvant and challenged with a pandemic H1N1 five weeks after the final vaccination. No vaccine/challenge groups (NV/C) showed signs of disease including fever, weight loss, lethargy, and coughing. However, the vaccine/challenge (V/C) groups of both swine and ferrets showed elevated clinical signs of disease over NV/C groups, despite similar viral loads in nasal swabs and lavage fluids. V/C pigs exhibited a 2-fold increase in macroscopic lung lesions compared to NV/C pigs, while V/C ferrets showed a 4-fold increase over NV/C ferrets. Serology and bronchoalveolar lavage fluid cytokine levels were also evaluated. These results indicate the VAERD phenomenon is not limited to swine, but can be replicated in ferrets, a standard animal model of human influenza.