Coinfections in the lung: How viral infection creates a favorable environment for bacterial and fungal infections
Joshua J. Obar, Kelly M. Shepardson
Abstract
While it is well established that secondary bacterial pneumonia plays a significant role in the morbidity and mortality of patients with severe respiratory viral infections, bacteria are not the only threat for these patients. Over the last decade, there has been a rise in the number of patients with severe respiratory viral infections acquiring secondary fungal infections, specifically with the filamentous mold Aspergillus fumigatus Importantly, while secondary fungal infections occur less frequently than secondary bacterial pneumonias, they are associated with greater mortality Because immune suppression is the major risk factor for acquiring fungal infections [3], severe respiratory viral infections may create a transient immune suppressed state allowing for these secondary infections to occur. Here, we discuss what we have learned about how antiviral host responses create a lung environment susceptible to bacterial infection and how this may translate into fungal susceptibility.