ABSTRACT
Newcastle disease virus (NDV) is a major threat to poultry worldwide. Virulent Newcastle disease virus infection can cause 100% morbidity and mortality in chickens. Vaccination is the most effective way to prevent and control NDV outbreaks in poultry. Previously, we demonstrated that a duck enteritis virus (DEV) vaccine strain is a promising vector to generate recombinant vaccines in chickens. Here, we constructed two recombinant DEVs expressing the F protein (rDEV-F) or HN protein (rDEV-HN) of NDV. We then evaluated the protective efficacy of these recombinant DEVs in specific-pathogen-free chickens. rDEV-F induced 100% protection of chickens from lethal NDV challenge after a single dose of 104 TCID50, whereas rDEV-HN did not induce effective protection. rDEV-F may therefore serve as a promising vaccine candidate for chickens. This is the first report of a DEV-vectored vaccine providing robust protection against lethal NDV infection in chickens.
