However, these vaccines may suffer from a limited immunogenicity and, in most cases, the protection induced is only partial. Subunit vaccines were developed to overcome these issues. Conventional vaccines based on live-attenuated pathogens present a risk of reversion to pathogenic virulence while inactivated pathogen vaccines often lead to a weak immune response. Vaccination is an affordable way to control the pathogenicity of viruses and constitutes the strategy of choice to fight against infections, including those leading to pulmonary diseases. These pathogens initially infect the upper respiratory tract and then reach the lower respiratory tract, leading to diseases. The respiratory mucosa is the primary portal of entry for numerous viruses such as the respiratory syncytial virus, the influenza virus and the parainfluenza virus. 4Faculté de Médecine Vétérinaire, Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Université de Montréal, St-Hyacinthe, QC, Canada.3Département des Sciences Biologiques, Université du Québec à Montréal, Montreal, QC, Canada.2Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO, Quebec, QC, Canada.1Département de Chimie, Université du Québec à Montréal, Montreal, QC, Canada.Soultan Al-Halifa 1,2, Laurie Gauthier 1,2,3,4, Dominic Arpin 1,2,3,4, Steve Bourgault 1,2,4 * and Denis Archambault 3,4*

Protein scaffold vaccine bacteria