Prolonged colonisation with Escherichia coli O25:ST131 versus other extended-spectrum beta-lactamase-producing E. coli in a long-term care facility with high endemic level of rectal colonisation, the Netherlands, 2013 to 2014

Abstract

The extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli clone ST131 (ESBL-ST131) has spread in healthcare settings worldwide. The reasons for its successful spread are unknown, but might include more effective transmission and/or longer persistence. We evaluated the colonisation dynamics of ESBL-producing E. coli (ESBL-EC), including ESBL-ST131, in a long-term care facility (LTCF) with an unusually high prevalence of rectal ESBL-EC colonisation. During a 14-month period, rectal or faecal samples were obtained from 296 residents during six repetitive prevalence surveys, using ESBL-selective culture. Transmission rates, reproduction numbers, and durations of colonisation were compared for ESBL-ST131 vs other ESBL-EC. Furthermore, the likely time required for ESBL-ST131 to disappear from the LTCF was estimated. Over time, the endemic level of ESBL-ST131 remained elevated whereas other ESBL-EC returned to low-level prevalence, despite comparable transmission rates. Survival analysis showed a half-life of 13 months for ESBL-ST131 carriage, vs two to three months for other ESBL-EC (p < 0.001). Per-admission reproduction numbers were 0.66 for ESBL-ST131 vs 0.56 for other ESBL-EC, predicting a mean time of three to four years for ESBL-ST131 to disappear from the LTCF under current conditions. Transmission rates were comparable for ESBL-ST131 vs other ESBL-EC. Prolonged rectal carriage explained the persistence of ESBL-ST131 in the LTCF.

Fecal carriage of extended spectrum β-lactamase producing Escherichia coli and Klebsiella pneumoniae after urinary tract infection – A three year prospective cohort study

“…Our major contributors to phylogroups B2/D are ST131 (n = 33) and ST38 (n = 13). In a previous study, ST131 has been associated with prolonged carriage in a cohort of long term health care facility residents [18], while other studies, like the present, do not find this correlation [15,17]. Our observation support the notion that also other strains than ST131 have potential to colonise the human intestine for a long time.…”

Responses of the Human Gut Escherichia coli Population to Pathogen and Antibiotic Disturbances

“…While we are unable to say for certain why the subjects in this study were colonized by ST131, studies have demonstrated high rates of colonization among people who have traveled to countries of endemicity or have stayed in long-term health care facilities and that CTX-M-containing ST131 clones have spread rapidly in the United States, where it is now a dominant lineage ( 35 , 38 – 41 ). Furthermore, ST131 is an efficient and prolonged colonizer, known to outcompete other resident strains and predicted to persist in the gastrointestinal tract for years ( 40 , 42 , 43 ), which may also help explain the readiness with which the resident E. coli population recovered following challenge and treatment.…”

Household Clustering of Escherichia coli Sequence Type 131 Clinical and Fecal Isolates According to Whole Genome Sequence Analysis

“…The 6-year persistence of an ST131- H 30Rx strain in household 4 equals or exceeds previous persistence records for commensal E coli , ie, 6 years [ 38 ], 3.9 years ( ), and 3 years [ 17 ]. Some evidence supports that ST131- H 30 strains may persist longer than other antimicrobial-resistant E coli [ 39 ], possibly promoting the ST131 pandemic. It is notable that the core genome of household 4's ST131- H 30Rx strain was quite stable over 6 years, consistent with the low background mutation rate of E coli , including ST131 [ 17 , 40 ].…”