IFNB1 and influenza: Several bacterial components or derived metabolites are involved in priming host innate immunity against respiratory viruses through IFNβ production, such as the lipo-oligosaccharides from Bacteroides in influenza infection [103] or acetate (and propionate or butyrate) from gut microbial metabolism, which is per se able to induce an IFNβ response in the lungs of mice and protect them from the respiratory syncytial virus when supplemented in drinking water [103].