Evaluation of two multi-locus sequence typing schemes for commensal Escherichia coli from dairy cattle in Washington State

Multi-locus sequence typing (MLST) is a useful system for phylogenetic and epidemiological studies of multidrug-resistant Escherichia coli. Most studies utilize a seven-locus MLST, but an alternate two-locus typing method (fumC and fimH; CH typing) has been proposed that may offer a similar degree of discrimination at lower cost. Herein, we compare CH typing to the standard seven-locus method for typing commensal E. coli isolates from dairy...