Comparing the Yield of Staphylococcus aureus Recovery with Static versus Agitated Broth Incubation
Table 1
Recovery of Staphylococcus aureus by culture method.
S. aureus strain
Culture method
Replicate, lowest dilution level of detection
Lowest dilution that was detected for all replicates, CFU/mL
1
2
3
Reference ATCC 25923 MSSA, SCCmec negative
Direct Plate
102
102
102
102
Static BE
10
102
103
≤103
Agitated BE
10
102
103
≤103
Reference ATCC 43300 MRSA, SCCmec type IV
Direct Plate
102
102
103
≤103
Static BE
102
10
102
≤102
Agitated BE
102
102
103
≤103
Clinical infecting isolate MRSA, SCCmec Type IV
Direct Plate
102
103
102
≤103
Static BE
102
103
102
≤103
Agitated BE
102
102
102
102
Clinical colonizing isolate MRSA, SCCmec Type II
Direct Plate
103
102
10
≤103
Static BE
103
102
102
≤103
Agitated BE
10
102
10
≤102
Clinical colonizing isolate MSSA, SCCmec Type IV
Direct Plate
102
102
102
102
Static BE
10
103
10
≤103
Agitated BE
10
102
102
≤102
CFU, colony forming unit; MRSA, methicillin-resistant S. aureus; MSSA, methicillin-susceptible S. aureus; SCCmec, staphylococcal cassette chromosome mec; BE, broth enrichment. Note. S. aureus was recovered at the 104 dilution for all strains and all culture methods at each replicate.