A Time Course for Susceptibility toStaphylococcus aureusRespiratory Infection during Influenza in a Swine Model

[摘要] Bacterial superinfections following influenza A virus (IAV) are predominant causes of morbidity in humans. The recent emergence of methicillin-resistantStaphylococcus aureus(MRSA) and highly virulent IAV strains has reduced treatment options. Development of an appropriate animal model to study secondaryS. aureusinfections may provide important information regarding disease pathogenesis. Pigs are natural hosts to both IAV andS. aureusand have respiratory physiology and immune response comparable to humans. To establish a time course of susceptibility toS. aureusafter IAV infection, nursery pigs infected intranasally with IAV were challenged with MRSA at different time points.Lung pathology scores and MRSA CFU were evaluated in dual-infected animals after IAV infection. Flow cytometric analysis of bronchoalveolar lavage fluid indicated differences between treatments. These results demonstrate the appropriateness of an intranasal challenge model in nursery pigs for studying the pathogenesis of IAV andS. aureuscoinfection and provide insights into the timeframe for susceptibility of IAV-infected pigs to secondaryS. aureusinfection.

[学科分类] 传染病学