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Volume 31, Number 6—June 2025

Research

Safety and Immunogenicity of Poultry Vaccine for Protecting Critically Endangered Avian Species against Highly Pathogenic Avian Influenza Virus, United States

Todd E. KatznerComments to Author , Ashleigh V. Blackford, Mary Donahue, Samantha E.J. Gibbs, Julianna Lenoch, Michael Martin, Tonie E. Rocke, J. Jeffrey Root, Darrel Styles, Sunny Cooper, Kristin Dean, Zachary Dvornicky-Raymond, Dominique Keller, Carlos Sanchez, Brett Dunlap, Thomas Grier, Michael P. Jones, Gregory Nitzel, Erin Patrick, Maureen Purcell, Aaron J. Specht, and David L. Suarez
Author affiliation: US Geological Survey, Forest and Rangeland Ecosystem Science Center, Boise, Idaho, USA (T.E. Katzner, M. Purcell); US Fish and Wildlife Service, California Condor Recovery Program, Vero Beach, Florida, USA (A.V. Blackford); US Department of Agriculture, Animal and Plant Health Inspection Service (APHIS) Veterinary Services, Minneapolis, Minnesota, USA (M. Donahue); US Fish and Wildlife Service, National Wildlife Refuge System, Wildlife Health Office, Chiefland, Florida, USA (S.E.J. Gibbs); US Department of Agriculture, APHIS Wildlife Services, National Wildlife Disease Program, Fort Collins, Colorado, USA (J. Lenoch); North Carolina Department of Agriculture and Consumer Services, Raleigh, North Carolina, USA (M. Martin); US Geological Survey, National Wildlife Health Center, Madison, Wisconsin, USA (T.E. Rocke); US Department of Agriculture, APHIS Wildlife Services, National Wildlife Research Center, Fort Collins (J.J. Root); US Department of Agriculture, APHIS Veterinary Services, Riverdale, Maryland, USA (D. Styles); Carolina Raptor Center, Huntersville, North Carolina, USA (S. Cooper, K. Dean); San Diego Zoo Wildlife Alliance, San Diego, California, USA (Z. Dvornicky-Raymond); Los Angeles Zoo and Botanical Garden, Los Angeles, California, USA (D. Keller); Oregon Zoo, Portland, Oregon, USA (C. Sanchez); US Department of Agriculture, APHIS Wildlife Services, Madison, Tennessee, USA (B. Dunlap); Purdue University School of Health Sciences, West Lafayette, Indiana, USA (T. Grier, A.J. Specht); American Eagle Foundation, Kodak, Tennessee, USA (M.P. Jones); Zoetis, Inc., Kalamazoo, Michigan, USA (G. Nitzel); US Department of Agriculture, APHIS Wildlife Services, Knoxville, Tennessee, USA (E. Patrick); US Department of Agriculture, Southeast Poultry Research Laboratory, Agricultural Research Service, Athens, Georgia, USA (D.L. Suarez)

Main Article

Table 1

Hemagglutination inhibition antibody titers in surrogate and target species in a study of safety and immunogenicity of poultry vaccine for protecting critically endangered avian species from highly pathogenic avian influenza virus, United States*

Time, dpv χ2 p value η2 Intergroup difference (p value)
HI titer [SD] (range) per vaccine regimen
 None–1 vaccine None–2 vaccines 1–2 vaccines
None, n = 8 1-vaccine, n = 10 2-vaccine, n = 10
Black vultures (Coragryps atratus)
10 0 [0.7] (0–2) 0 [5.1] (0–16) 0 [81.0] (0–256) 0.01 0.994 −0.08 NA NA NA
21 0 32 [96.8] (0–256) 16 [82.9] (0–256) 9.65 0.008 0.31 −3.09 (0.006) −2.019 (0.130) 1.13 (0.774)
31 0 96 [75.6] (0–256) 64 [40.5] (32–128) 16.01 <0.001 0.56 −3.50 (0.001) −3.55 (0.001) −0.06 (1.00)
42
 0
64 [73.6] (0–256)
 128 [180.5] (0–512)
 16.26
 <0.001
 0.57
 −2.71 (0.020)
 −3.99 (<0.001)
 −1.35 (0.528)
California condors (Gymnogyps californianus)
21 0 16 [19.3] (0–64) 4 [11.0] (0–32) 7.49 0.024 0.25 −2.72 (0.020) −1.59 (0.334) 1.38 (0.501)
42† 0 12 [7.9] (0–16) 32 [20.3] (0–64) 7.42 0.025 0.25 −1.40 (0.484) −2.71 (0.0203) −1.23 (0.656)

*Bold text indicates statistical significance. Birds were vaccinated with a 1057.R1 serial 590088 Avian Influenza Vaccine, H5N1 subtype, reverse genetics-derived, inactivated vaccine. See main text for details on the vaccine and vaccination regimens. Titers were compared by using Kruskal-Wallis test reporting a χ2, a p value, and an effect estimate (η2); degrees of freedom = 2 in all tests and, when different, a Dunn’s multiple comparison (reporting a Z statistic and a p value). dpv, days postvaccination; HI, hemagglutination inhibition; NA, no difference detected so multiple comparison not relevant. †For day 42, HI titers are only available for 6 condors given a single vaccination.

Main Article

Page created: April 03, 2025
Page updated: May 27, 2025
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