A CD-1 mouse model of infection with Staphylococcus aureus: influence of gender on infection with MRSA and MSSA isolates.

Staphylococcus aureus is an important pathogen of humans and other animals, causing bacteremia, abscessation, toxemia, and other infectious diseases. An animal model using CD-1 mice was developed to study the pathogenesis of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA). When inoculated into the CD-1 mouse model, it was shown that both MSSA isolates, (HR 78 and CSA-1) and MRSA isolates (MRSA 456 and MRSA 457) led to chronic infection of the kidney. Female CD-1 mice inoculated with MRSA 456 proved to be more susceptible to infection and mortality than their male counterparts. Castrated mice became more susceptible to infection than intact male mice, suggesting a hormonal involvement in the infection process.