Using diapers, the prevalence of ESBL-producing Enterobacteriaceae in children was quickly established, and, most likely, a transmission of ESBL-producing E. coli was for the first time documented between children at the same preschool.

By collecting and analyzing diapers, we identified a >6-fold increase in carriage of extended-spectrum β-lactamase (ESBL)–producing Enterobacteriaceae for healthy preschool children in Sweden (p<0.0001). For 6 of the 50 participating preschools, the carriage rate was >40%. We analyzed samples from 334 children and found 56 containing >1 ESBL producer. The prevalence in the study population increased from 2.6% in 2010 to 16.8% in 2016 (p<0.0001), and for 6 of the 50 participating preschools, the carriage rate was >40%. Furthermore, 58% of the ESBL producers were multidrug resistant, and transmission of ESBL-producing and non–ESBL-producing strains was observed at several of the preschools. Toddlers appear to be major carriers of ESBL producers in Sweden.

No abstract

Preschool children in Uppsala do not constitute a reservoir for VRE. The zero prevalence is consistent with the overall decline in VRE prevalence in Sweden during the last years.