Polymicrobial Infection

Host Response, Viral Infection, and Bacterial Pneumonia

Several lines of evidence -- experimental, clinical and epidemiological -- suggest that influenza infection increases risk of bacterial pneumonia with Streptococcus pneumoniae and with Staphylococcus aureus, including methicillin resistant S. aureus (MRSA). We are distilling known empirical information into a mathematical model to explore the interactions among influenza, S. pneumoniae and S. aureus that lead to pneumonia at the individual and population levels. In the short run, the modeling exercise will identify gaps in our knowledge, and serve as a basis for designing studies to fill those gaps. In the long run, the model will help us understand how these interactions lead to pneumonia, and to predict the effects of interventions directed at reducing influenza, S. pneumoniae and S. aureus on the incidence of pneumonia.