Protection and differentiation of infected from vaccinated animals by an inactivated recombinant Newcastle disease virus/avian influenza H5 vaccine.
Specific-pathogen-free chickens immunized at 14 days of age with either an inactivated recombinant Newcastle disease virus-LaSota/avian influenza H5 (K-rNDV-LS/AI-H5) vaccine or a killed Newcastle disease/avian influenza whole-virus vaccine (K-ND/AI) were protected from disease when challenged with either A/chicken/Queretaro/14588-19/95 (H5N2), a high pathogenicity avian influenza virus (HPAIV) strain isolated in Mexico in 1995, or with a Mexican velogenic viscerotropic Newcastle disease virus (VVNDV) strain 21 days postvaccination. All nonvaccinated chickens challenged with HPAIV or VVNDV succumbed to disease, while those vaccinated with K-rNDV-LS/AI-H5 or K-ND/AI were protected from severe clinical signs and death. Both vaccines induced hemagglutination-inhibition (HI) antibody responses against NDV and AIV. Antibodies against AIV nucleoprotein were not detected by enzyme-linked immunosorbent assay (ELISA) in birds vaccinated with the inactivated rNDV-LS/AI-H5 vaccine. These chickens became positive for AIV antibodies by ELISA only after challenge with HPAIV. The data clearly indicate that the inactivated rNDV-LS/AI-H5 vaccine confers protection comparable to that of the conventional killed whole-virus vaccine against both NDV and AIV, while still allowing differentiation of infected from vaccinated animals by HI and ELISA tests.
Laboratorio Avi-Mex, SA de CV, Bartolache 1862, Colonia del Valle, 01900, México, D.F. México.
Bernardo
B
Lozano-Dubernard
Ernesto
E
Soto-Priante
David
D
Sarfati-Mizrahi
Felipa
F
Castro-Peralta
Ricardo
R
Flores-Castro
Elizabeth
E
Loza-Rubio
Manuel
M
Gay-Gutiérrez
D000818:Animals; D002645:Chickens; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000276:immunology*; D005585:Influenza in Birds / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D008297:Male; D009521:Newcastle Disease / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D009522:Newcastle disease virus / Q000276:immunology*; D013047:Specific Pathogen-Free Organisms; D015164:Vaccines, Inactivated / Q000276:immunology; D014614:Vaccines, Synthetic / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology*
D019267:Hemagglutinin Glycoproteins, Influenza Virus; D015164:Vaccines, Inactivated; D014614:Vaccines, Synthetic; D014765:Viral Vaccines; C109963:hemagglutinin, avian influenza A virus