TY - JOUR

T1 - Vaccination of poultry against highly pathogenic avian influenza – part 1. Available vaccines and vaccination strategies

AU - Nielsen, Søren Saxmose

AU - Alvarez, Julio

AU - Bicout, Dominique Joseph

AU - Calistri, Paolo

AU - Canali, Elisabetta

AU - Drewe, Julian Ashley

AU - Garin-Bastuji, Bruno

AU - Gonzales Rojas, Jose Luis

AU - Gortázar, Christian

AU - Herskin, Mette

AU - Michel, Virginie

AU - Miranda Chueca, Miguel Ángel

AU - Padalino, Barbara

AU - Roberts, Helen Clare

AU - Spoolder, Hans

AU - Stahl, Karl

AU - Velarde, Antonio

AU - Winckler, Christoph

AU - Bastino, Eleonora

AU - Bortolami, Alessio

AU - Guinat, Claire

AU - Harder, Timm

AU - Stegeman, Arjan

AU - Terregino, Calogero

AU - Aznar Asensio, Inmaculada

AU - Mur, Lina

AU - Broglia, Alessandro

AU - Baldinelli, Francesca

AU - Viltrop, Arvo

AU - EFSA Panel on Animal Health and Animal Welfare (AHAW), European Union Reference Laboratory for Avian Influenza

N1 - Publisher Copyright: © 2023 European Food Safety Authority. EFSA Journal published by Wiley-VCH GmbH on behalf of European Food Safety Authority.

PY - 2023

Y1 - 2023

N2 - Several vaccines have been developed against highly pathogenic avian influenza (HPAI), mostly inactivated whole-virus vaccines for chickens. In the EU, one vaccine is authorised in chickens but is not fully efficacious to stop transmission, highlighting the need for vaccines tailored to diverse poultry species and production types. Off-label use of vaccines is possible, but effectiveness varies. Vaccines are usually injectable, a time-consuming process. Mass-application vaccines outside hatcheries remain rare. First vaccination varies from in-ovo to 6 weeks of age. Data about immunity onset and duration in the target species are often unavailable, despite being key for effective planning. Minimising antigenic distance between vaccines and field strains is essential, requiring rapid updates of vaccines to match circulating strains. Generating harmonised vaccine efficacy data showing vaccine ability to reduce transmission is crucial and this ability should be also assessed in field trials. Planning vaccination requires selecting the most adequate vaccine type and vaccination scheme. Emergency protective vaccination is limited to vaccines that are not restricted by species, age or pre-existing vector-immunity, while preventive vaccination should prioritise achieving the highest protection, especially for the most susceptible species in high-risk transmission areas. Model simulations in France, Italy and The Netherlands revealed that (i) duck and turkey farms are more infectious than chickens, (ii) depopulating infected farms only showed limitations in controlling disease spread, while 1-km ring-culling performed better than or similar to emergency preventive ring-vaccination scenarios, although with the highest number of depopulated farms, (iii) preventive vaccination of the most susceptible species in high-risk transmission areas was the best option to minimise the outbreaks' number and duration, (iv) during outbreaks in such areas, emergency protective vaccination in a 3-km radius was more effective than 1- and 10-km radius. Vaccine efficacy should be monitored and complement other surveillance and preventive efforts.

AB - Several vaccines have been developed against highly pathogenic avian influenza (HPAI), mostly inactivated whole-virus vaccines for chickens. In the EU, one vaccine is authorised in chickens but is not fully efficacious to stop transmission, highlighting the need for vaccines tailored to diverse poultry species and production types. Off-label use of vaccines is possible, but effectiveness varies. Vaccines are usually injectable, a time-consuming process. Mass-application vaccines outside hatcheries remain rare. First vaccination varies from in-ovo to 6 weeks of age. Data about immunity onset and duration in the target species are often unavailable, despite being key for effective planning. Minimising antigenic distance between vaccines and field strains is essential, requiring rapid updates of vaccines to match circulating strains. Generating harmonised vaccine efficacy data showing vaccine ability to reduce transmission is crucial and this ability should be also assessed in field trials. Planning vaccination requires selecting the most adequate vaccine type and vaccination scheme. Emergency protective vaccination is limited to vaccines that are not restricted by species, age or pre-existing vector-immunity, while preventive vaccination should prioritise achieving the highest protection, especially for the most susceptible species in high-risk transmission areas. Model simulations in France, Italy and The Netherlands revealed that (i) duck and turkey farms are more infectious than chickens, (ii) depopulating infected farms only showed limitations in controlling disease spread, while 1-km ring-culling performed better than or similar to emergency preventive ring-vaccination scenarios, although with the highest number of depopulated farms, (iii) preventive vaccination of the most susceptible species in high-risk transmission areas was the best option to minimise the outbreaks' number and duration, (iv) during outbreaks in such areas, emergency protective vaccination in a 3-km radius was more effective than 1- and 10-km radius. Vaccine efficacy should be monitored and complement other surveillance and preventive efforts.

KW - Highly pathogenic avian influenza (HPAI)

KW - poultry

KW - vaccines

KW - vaccine efficacy

KW - avian influenza transmission

KW - vaccination strategies

U2 - 10.2903/j.efsa.2023.8271

DO - 10.2903/j.efsa.2023.8271

M3 - Journal article

C2 - 37822713

VL - 21

JO - E F S A Journal

JF - E F S A Journal

SN - 1831-4732

IS - 10

M1 - e08271

ER -