Virulence characteristics of wildtype ST93 CA-MRSA isolates. S. aureus JKD6159 compared with three other wildtype ST93 CA-MRSA isolates, TPS3104, TPS3105 and TPS3106 in a BALB/c mouse skin infection assay. At least 10 mice were used for each bacterial strain. (A) Weight loss induced by intradermal infection with S. aureus strains is demonstrated as percentage loss of weight over 5 days. The difference in percentage weight loss between JKD6159 and TPS3105 and TPS3106 was significant (p < 0.0001). There was no difference in weight loss between JKD6159 and TPS3104. Data shown are mean weight loss and SEM. (B) Skin lesion area (mm2) at 5 days after infection was significantly greater with JKD6159 infected mice compared to TPS3105 and TPS3106 (p < 0.0001). There was no difference in lesion area between JKD6159 and TPS3104. Data shown are mean area and SEM. (C) Recovery of S. aureus (log CFU) from infected tissues at 5 days after infection from JKD6159 infected mice was greater than with TPS3105 (p = 0.0177) and TPS3106 infected mice (p = 0.0328). There was no difference between JD6159 and TPS3104 infected mice. Data shown are mean CFU and SEM. Note, ***p < 0.001, *p < 0.05.
Chua et al. BMC Microbiology 2014 14:31 doi:10.1186/1471-2180-14-31