Fosfomycin resistance in Escherichia coli is rare in the United States. An extended-spectrum β-lactamase-producing E. coli clinical strain identified in Pennsylvania, USA, showed high-level fosfomycin resistance caused by the fosA3 gene. The IncFII plasmid carrying this gene had a structure similar to those found in China, where fosfomycin resistance is commonly described.
Keywords: 16S rRNA methyltransferase; ESBL; Escherichia coli; Pennsylvania; United States; antimicrobial resistance; bacteria; extended-spectrum β-lactamase; fosA3 gene; fosfomycin resistance; glutathione S-transferase; plasmids.