Abstract Title
A turkey herpesvirus vectored vaccine protects commercial turkeys against highly pathogenic avian influenza H5 clade 2.3.4.4b
Abstract
Turkey (Meleagris gallopavo) is one of the most susceptible species to highly pathogenic avian influenza (HPAI) among domestic poultry. Beyond biosecurity and sanitation, vaccination is nowadays regarded as a relevant additional tool to protect birds against the disease to reduce the amount of culling thanks to an improved shedding control and ultimately to protect public health. Publicly available information about vaccine efficacy in turkeys against the currently circulating HPAIV H5 2.3.4.4b clade is scarce.
A rHVT-H5 vaccine is commercially available and used in several countries around the world against H5Nx HPAI in chickens. Our study aimed at testing the efficacy of this vaccine in turkeys against a recent European HPAI H5 virus strain of 2.3.4.4b clade.
Forty commercial turkey poults were vaccinated at day-old; twenty of them were challenged through the intra-nasal route at seven weeks of age, whereas the remaining twenty were kept as contacts. Twenty non-vaccinated controls were directly challenged (10) or kept as contacts (10) in a similar way.
Post-challenge clinical observation was fourteen days long. Oro-pharyngeal as well as cloacal swabs were collected on days 2, 3, 4, and 7 post-challenge for virus detection and quantification. Blood samples were collected and tested by HI test and by H5 and NP ELISA tests.
There was a 100% mortality in controls whereas all vaccinated turkeys survived, regardless the challenge route. A significant shedding reduction was measured in vaccinated birds compared to controls. Altogether, the data showed a satisfactory efficacy of the vaccine in turkeys.
A rHVT-H5 vaccine is commercially available and used in several countries around the world against H5Nx HPAI in chickens. Our study aimed at testing the efficacy of this vaccine in turkeys against a recent European HPAI H5 virus strain of 2.3.4.4b clade.
Forty commercial turkey poults were vaccinated at day-old; twenty of them were challenged through the intra-nasal route at seven weeks of age, whereas the remaining twenty were kept as contacts. Twenty non-vaccinated controls were directly challenged (10) or kept as contacts (10) in a similar way.
Post-challenge clinical observation was fourteen days long. Oro-pharyngeal as well as cloacal swabs were collected on days 2, 3, 4, and 7 post-challenge for virus detection and quantification. Blood samples were collected and tested by HI test and by H5 and NP ELISA tests.
There was a 100% mortality in controls whereas all vaccinated turkeys survived, regardless the challenge route. A significant shedding reduction was measured in vaccinated birds compared to controls. Altogether, the data showed a satisfactory efficacy of the vaccine in turkeys.
Co-Author(s)
T. Tatar-Kis1, E. Walko-Kovacs1, I. Kiss1, G. Dauphin2, J. de Foucauld2, C. Cazaban2, S. Comte2
1: Ceva Animal Health, Budapest, Hungary; 2: Ceva Animal Health, Libourne, France.
Abstract Category
Diagnostics, vaccination, or other mitigation strategies for poultry and wildlife