Virulence Potential of ESBL-Producing Escherichia coli Isolated during the Perinatal Period.

The aim of the study was to investigate the virulence factors in Escherichia coli producing extended-spectrum β-lactamase (ESBL) derived from the perinatal fecal colonization flora of mothers and their newborns in a Chinese obstetric ward.Rectal swabs were obtained from mothers prenatally and from their newborns postnatally, and analyzed for ESBL-producing Escherichia coli. The isolates were then whole-genome sequenced.Maternal and neonatal colonization by ESBL-producing E. coli in a Chinese obstetric ward was 18% (31/177) and 5% (9/170), respectively. Fecal ESBL-producing isolates exhibited a significantly lower frequency of virulence factors compared with invasive E. coli.Providing balanced information on screening results is essential, along with conducting a risk assessment for antibiotic treatment strategies. · High ESBL E. coli colonization rates in mothers and neonates perinatally. · Fecal ESBL-producing E. coli showed fewer virulence traits.. · ESBL-producing E. coli knowledge may prompt antibiotic overuse..