Figure 1.

Shifts in the mouse gut microbiome in the setting of influenza infection. During an acute respiratory viral infection, changes in the bacterial composition of the gut microbiome can be observed despite the absence of detectable virus in the gastrointestinal compartment. This suggests that systemic immune signals, physiologic changes (e.g., weight loss), and other still unknown factors are disrupting the normal ecology of the gut, thereby leading to dysbiosis. However, the majority of these studies have been conducted in laboratory animals housed under SPF conditions. It remains to be determined whether human patients and mammalian hosts with more diverse baseline gut microbiota (i.e., mice in the wild), exhibit similar qualitative or quantitative changes.