Increase in Escherichia coli isolates carrying blaNDM-5 in the European Union/European Economic Area, 2012–2022

Unpublished preliminary results of the survey of carbapenem- and/or colistin-resistant Enterobacterales (CCRE- survey) conducted in 36 European countries in 2019 had shown that NDM-5 had become the most frequently reported carbapenemase in Escherichia coli. The aim of this study was to determine the extent of the spread of E. coli isolates carrying blaNDM-5 in the European Union/European Economic Area (EU/EEA). Analysis of whole genome sequencing and epidemiological data of 874 E. coli isolates from the national collections of 13 countries confirmed the increase of E. coli isolates carrying blaNDM-5 which was previously detected in the CCRE survey.

While the blaNDM-5 gene was detected in 83 different E. coli sequence types (STs) from national collections, there was a strong predominance of a few STs, mainly ST167, ST405, ST410, ST361, and ST648. The high number and the large size of multi-country clusters in the dataset, including recent isolates from 2022, suggest an ongoing rapid global expansion of these dominant E. coli STs carrying blaNDM-5, including the EU/EEA.

Despite limited data completeness, about 84.2% of the E. coli isolates carrying blaNDM-5 with available information on travel and/or hospitalisation within the six months before sampling were linked to a country outside of the EU/EEA, mainly countries in Africa and Asia. This suggests that travel-related acquisition may still be the most likely origin of these isolates. Additionally, about 30% of the E. coli isolates carrying blaNDM-5 were documented as related to infections, emphasising the clinical relevance and need for early detection.

Furthermore, a high proportion of the isolates carrying blaNDM-5 also co-harboured resistance markers to aminoglycosides, fluoroquinolones, and trimethoprim-sulfamethoxazole, indicating multidrug resistance with limited options left for the treatment of patients.

Further spread of E. coli isolates carrying blaNDM-5 within and between the EU/EEA countries, particularly in healthcare facilities, as well as introductions from outside of the EU/EEA have the potential to increase dissemination, with severe consequences on the health-related and economic burden caused by these infections. Due to resistance to carbapenems as well as other antibiotics, such a scenario would leave limited options for the treatment of E. coli infections, both in healthcare and community.