Antimicrobial Resistance in Enteric Bacteria

Antimicrobial resistance (AMR) among enteric bacteria poses a critical threat to global public health, undermining the effectiveness of frontline therapies for infections caused by Escherichia coli, Salmonella spp., Shigella spp. and other gut‐associated pathogens. Resistance arises through chromosomal mutations, acquisition of mobile genetic elements and horizontal gene transfer, leading to enzymatic degradation of antibiotics, target modification, reduced permeability and active efflux. The dissemination of extended‐spectrum β-lactamases, carbapenemases and colistin‐resistance determinants has been accelerated by intensive agricultural antibiotic use, inadequate sanitation, international travel and uneven surveillance efforts. A One Health perspective highlights the interconnectedness of human, animal and environmental reservoirs, where antimicrobial consumption in livestock, aquaculture and clinical settings selects for multidrug‐resistant clones that can colonise and infect diverse hosts. Epidemiological trends reveal a steady increase in resistant infections in low- and middle-income countries, often exacerbated by poverty, malnutrition and limited access to second-line treatments. Advances in genomic epidemiology, functional genomics and ecological modelling are beginning to unravel the genetic networks and ecological drivers that underpin resistance evolution. These insights inform novel intervention strategies, including targeted stewardship in agriculture, improved wastewater management, rapid molecular diagnostics and the design of next-generation antimicrobials that circumvent existing resistance mechanisms.

Research from Nature Portfolio

Analyses of the global distribution and evolution of the colistin‐resistance gene mcr-1 have revealed that all circulating variants descend from a single mobilisation event by an ISApl1 transposon in the early 2000s, followed by rapid demographic expansion across diverse plasmid backbones. Phylogenetic reconstruction of over 450 mcr-1-positive isolates identified a common ancestral sequence and traced its dissemination across continents, underscoring the critical role of mobile elements in the global spread of last-resort resistance. These findings provide a temporal framework for surveillance and highlight key genomic contexts that could be targeted to disrupt transmission.

Antimicrobial Resistance in Enteric Bacteria publication trend

The graph below shows the total number of articles in antimicrobial resistance in enteric bacteria across all publications each year (not limited to Nature Index journals).

Technical terms

Plasmid: A self-replicating circular DNA molecule that can transfer between bacteria, often carrying resistance genes.

Transposon: A mobile DNA element capable of moving within and between genomes, facilitating the spread of resistance determinants.

One Health: An integrative approach recognising that human, animal and environmental health are interconnected in the emergence and dissemination of AMR.

Extended-spectrum β-lactamase (ESBL): An enzyme that confers resistance to a wide range of β-lactam antibiotics, including penicillins and cephalosporins.

References

1. Global antimicrobial-resistance drivers: an ecological country-level study at the human–animal interface. The Lancet Planetary Health (2023).
2. The global distribution and spread of the mobilized colistin resistance gene mcr-1. Nature Communications (2018).
3. Antibiotic Use in Agriculture and Its Consequential Resistance in Environmental Sources: Potential Public Health Implications. Molecules (2018).