“…The symbiotic microbiota, which consists of trillions of microorganisms, plays a crucial role in regulating various host physiological functions, such as digestion, nutrient metabolism, and immune system development [ 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 ]. Recently, mounting evidence has suggested that the gut microbiota modulates the host’s susceptibility to viral infections and contributes to various immune protective mechanisms against influenza virus infection [ 18 , 19 , 20 , 88 , 139 , 140 , 141 , 142 , 143 , 144 , 145 ]. Neomycin-sensitive bacterial communities continuously provide signals for the transcription of Il1b and Il18 , contributing to pulmonary protective immune responses during influenza virus infection [ 18 , 139 ].…”