Immediate Appearance of Plasmid-Mediated Resistance to Multiple Antibiotics upon Antibiotic Selection: an Argument for Systematic Resistance Epidemiology

We describe a conjugative plasmid appearing in a bacteremic clone of Escherichia coli immediately upon exposure to the antibiotics for which it encoded resistance. Effective antibiotic choice was made possible by prior screening for this plasmid. Surveillance for transmissible resistance plasmids may be clinically important.