Preliminary insights on carbapenem resistance in Enterobacteriaceae in high-income and low-/middle-income countries.

The emergence of carbapenem-resistant Enterobacteriaceae in the hospital sector as well as in the natural environment is a problem that affects both high-income countries (HICs) and low-/middle-income countries (LMICs). The observed differences in the prevalence of carbapenem-resistant strains between HICs and LMICs can be attributed mainly to antibiotic consumption in healthcare facilities and the quantity of treated wastewater. Hospital wastewater is a major hotspot for the spread of carbapenem-resistant Enterobacteriaceae (CRE) and carbapenem resistance genes (CRGs) between the hospital sector and the environment. In this review article, attempts were made to describe and compare antibiotic consumption in hospitals, antimicrobial concentrations in both hospital and municipal wastewater, and the prevalence of CRE and CRGs in patients and in hospital and municipal wastewater in HICs and LMICs. A review of the literature has shown that carbapenems are more widely used in LMICs, but Saudi Arabia, an HIC, is a country with the highest carbapenem consumption in the world. The results of research conducted in both groups of countries indicate that Klebsiella sp./K. pneumoniae is the most common CRE in samples isolated from patients. Escherichia coli was the dominant pathogen in hospital and municipal wastewater in HICs, whereas Enterobacter spp. were most prevalent in LMICs. An analysis of the prevalence of CRGs demonstrated that the same genes are present in both groups of countries (blaKPC, blaKPC-2, blaVIM, blaVIM-1,2, blaNDM, blaIMP, blaIMP-8, blaOXA-48,181, blaNDM-1,5, blaGES, blaGES-5,6, blaIMI-1). The fact that the same CRGs are most prevalent in countries with different levels of economic development could suggest that these genes have a high potential to persist in the natural environment. These findings underscore the need for enhanced monitoring, effective control techniques, and a better understanding of carbapenem resistance pathways to mitigate public health hazards, notwithstanding the constraints of data analysis.