Ferrets as a mammalian model to study influenza virus-bacteria interactions.

Ferrets represent an invaluable model for the study of influenza virus pathogenicity and transmissibility due to the ability of this species to recapitulate clinical symptoms of influenza infection present in humans. Ferrets are also employed for the study of bacterial pathogens that naturally infect humans at different anatomical sites, including the respiratory and gastrointestinal tracts. While viral and bacterial infection studies in isolation using animal models are important for furthering our understanding of pathogen biology and for the development of improved therapeutics, it is also critical to extend our knowledge to pathogen coinfections in vivo, to more closely examine interkingdom dynamics that may contribute to overall disease outcomes. Despite the increasing use of ferrets for studies with influenza virus, few reports have investigated influenza and bacterial coinfection challenges in ferrets. In this review, we discuss how ferrets have been employed to study a diverse range of both influenza viruses and bacterial species and summarize key studies that have utilized the ferret model for primary influenza virus challenge followed by secondary bacterial infection. These co-pathogenesis studies have provided critical insight into the dynamic interplay between these pathogens, underscoring the utility of ferrets as a model system for investigating influenza virus-bacteria interactions.