The cytopathic effect of the influenza virus on the tracheobronchial epithelium may predispose to secondary bacterial pneumonia [11, 12] . Secondary bacterial pneumonia must be suspected whenever there is an exacerbation of fever and respiratory symptoms after initial improvement in a patient diagnosed with acute influenza. Leukocytosis, instead of a normal or low white blood cell count, and lobar consolidation on chest imaging, instead of the diffuse pattern that is typical of viral pneumonia, are also suggestive [13] .