Abstract Title
Field serological monitoring of mule ducks vaccinated against highly pathogenic avian influenza with a self-amplifying mRNA vaccine in France: importance of the quality of vaccination and vaccine uptake
Abstract
Highly pathogenic avian influenza (HPAI) has severely impacted poultry production in France for the last eight years. French authorities were the only ones in Europe to choose vaccination as a complementary tool for controlling HPAI in commercial duck production.
The novel self-amplifying mRNA vaccine technology represents a breakthrough in animal health vaccines use. Beyond efficacy and viral shedding reduction expectation, this fully synthetic vaccine aligns perfectly with the differentiating infected from vaccinated animals’ strategy (DIVA). To provide guidelines of such a vaccine to the users in the field, it is essential to establish serological response standards.
Enzootic disease control through vaccination can only be ensured if the vaccination quality is suitable. Therefore, monitoring vaccination uptake in various field conditions using accessible tool, namely serology is a crucial issue.
Ten commercial mule ducks flocks (60,000 ducks) were included in a field serological monitoring study. Ducklings were vaccinated with a self-amplifying mRNA vaccine at day 1 and before day 28 by intra-muscular route.
Blood was collected from 20 random ducks every two weeks; sera were tested using a commercial Indirect H5 Elisa kit. Post-vaccination antibody titers showed a strong and rapid seroconversion 1 to 2 weeks after the booster. After this peak, a slow antibody detection decrease was observed until the study’s end.
Thanks to this field investigation, an optimal blood sampling window has been set to assess the whole vaccination program quality. This will provide standards for the control and evaluation of vaccination uptake from now on in mule duck flocks.
The novel self-amplifying mRNA vaccine technology represents a breakthrough in animal health vaccines use. Beyond efficacy and viral shedding reduction expectation, this fully synthetic vaccine aligns perfectly with the differentiating infected from vaccinated animals’ strategy (DIVA). To provide guidelines of such a vaccine to the users in the field, it is essential to establish serological response standards.
Enzootic disease control through vaccination can only be ensured if the vaccination quality is suitable. Therefore, monitoring vaccination uptake in various field conditions using accessible tool, namely serology is a crucial issue.
Ten commercial mule ducks flocks (60,000 ducks) were included in a field serological monitoring study. Ducklings were vaccinated with a self-amplifying mRNA vaccine at day 1 and before day 28 by intra-muscular route.
Blood was collected from 20 random ducks every two weeks; sera were tested using a commercial Indirect H5 Elisa kit. Post-vaccination antibody titers showed a strong and rapid seroconversion 1 to 2 weeks after the booster. After this peak, a slow antibody detection decrease was observed until the study’s end.
Thanks to this field investigation, an optimal blood sampling window has been set to assess the whole vaccination program quality. This will provide standards for the control and evaluation of vaccination uptake from now on in mule duck flocks.
Co-Author(s)
F. Lavigne1,2*, S. Castagnos1, E. Moreau1, C. Caudron1, T. Langlade1, B. Mousset1, C. Cazaban1, J.L Guerin2, S. Comte1.
1 : Ceva Animal Health, Libourne, France; 2 : Toulouse Veterinary University , Toulouse, France.
*PhD student.
Abstract Category
Diagnostics, vaccination, or other mitigation strategies for poultry and wildlife