Use of a tetanus toxoid marker to allow differentiation of infected from vaccinated poultry without affecting the efficacy of a H5N1 avian influenza virus vaccine.
Tetanus toxoid (TT) was assessed as a positive marker for avian influenza (AI) virus vaccination in chickens, in a vaccination and challenge study. Chickens were vaccinated twice with inactivated AI H5N2 virus vaccine, and then challenged three weeks later with highly pathogenic AI H5N1 virus. Vaccinated chickens were compared with other groups that were either sham-vaccinated or vaccinated with virus with the TT marker. All sham-vaccinated chickens died by 36 hours postinfection, whereas all vaccinated chickens, with or without the TT marker, were protected from morbidity and mortality following exposure to the challenge virus. Serological testing for H5-specific antibodies identified anamnestic responses to H5 in some of the vaccinated birds, indicating active virus infection.
Faculty of Health Sciences, School of Veterinary and Biomedical Sciences, Murdoch University, 90 South Street, Perth 6150, Western Australia, Australia. c.berry@murdoch.edu.au
C M
CM
James-Berry
D
D
Middleton
J P
JP
Mansfield
S G
SG
Fenwick
T M
TM
Ellis
D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis / Q000096:biosynthesis; D015415:Biomarkers / Q000032:analysis; D002645:Chickens; D005260:Female; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage*; D005585:Influenza in Birds / Q000276:immunology / Q000517:prevention & control*; D008297:Male; D011897:Random Allocation; D013047:Specific Pathogen-Free Organisms; D013745:Tetanus Toxoid / Q000032:analysis*; D015164:Vaccines, Inactivated / Q000008:administration & dosage
D000914:Antibodies, Viral; D015415:Biomarkers; D007252:Influenza Vaccines; D013745:Tetanus Toxoid; D015164:Vaccines, Inactivated