Protective efficacy of commercial inactivated Newcastle disease virus vaccines in chickens against a recent Korean epizootic strain

• Published in: Journal of veterinary science (Suwŏn-si, Korea) 2008, 9(3), , pp.295-300
• Main Authors: Jeon, W.J. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), Lee, E.K. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), Lee, Y.J. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), Jeong, O.M. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), Kim, Y.J. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), Kwon, J.H. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), Choi, K.S. (National Veterinary Research and Quarantine Service, Anyang, Republic of Korea), E-mail: [e-mail]
• Format: Article
• Language: English
• Subjects: Administration, Intranasal; Animals; Chickens; Cloaca - virology; Disease Outbreaks - prevention & control; Disease Outbreaks - veterinary; ENFERMEDAD DE NEWCASTLE; Korea; MALADIE DE NEWCASTLE; NEWCASTLE DISEASE; Newcastle Disease - immunology; Newcastle Disease - prevention & control; Newcastle disease virus - immunology; Ophthalmic Solutions; Original; Poultry Diseases - immunology; Poultry Diseases - prevention & control; protection; VACCINATION; Vaccines, Inactivated - administration & dosage; VACUNACION; Viral Vaccines - administration & dosage; virus shedding; Virus Shedding - drug effects; 수의학
• ISSN: 1229-845X; 1976-555X
• DOI: 10.4142/jvs.2008.9.3.295

Despite the intensive vaccination policy that has been put in place to control Newcastle disease virus (NDV), the recent emergence of NDV genotype Ⅶ strains in Korea has led to significant economic losses in the poultry industry. We assessed the ability of inactivated, oil-emulsion vaccines derived from La Sota or Ulster 2C NDV strains to protect chickens from challenge with Kr-005/00, which is a recently isolated Korean epizootic genotype Ⅶ strain. Six-week-old SPF chickens were vaccinated once and challenged three weeks later via the eye drop/intranasal route. All vaccinated birds were fully protected from disease, regardless of the vaccine strains used. All vaccinated and challenged groups showed significant sero-conversion 14 days after challenge. However, some vaccinated birds, despite being protected from disease, shed the challenge virus from their oro-pharynx and cloaca, albeit at significantly lower titers than the unvaccinated challenged control birds. The virological, serological, and epidemiological significance of our observations with regard to NDV disease eradication is discussed.