Resistant microorganisms (such as bacteria or fungi), and the high difficulty in finding a suitable therapy to eradicate infections directly related to them, are two of the most serious problem that the World is presently facing.

In fact, scientists are involved in several challenges, for example, searching for new drugs, exploring natural products, and others try to revert this resistance to make the common drugs work again.

Klebsiella pneumoniae is a Gram-negative microorganism and it has been related to the emergence of resistance to carbapenems, one of the drugs only used on severe or high-rick bacterial infections. Last week, researchers from the UK, Germany and Italy revealed a critical threat. The authors studied approximately 1700 clinical isolates of K. pneumoniae from hospitals in 32 countries. They indicated that within-hospital transmission occurred in over half of the hospitals with carbapenemase-positive isolates, aggravating the resistance patterns, but also concluding that interhospital spread is more recurrent within countries.

The rise and propagation of carbapenem-resistance among Enterobacteriaceae, particularly Klebsiella pneumoniae, constitute a serious threat to health.

Abstract

Public health interventions to control the current epidemic of carbapenem-resistant Klebsiella pneumoniae rely on a com-prehensive understanding of its emergence and spread over a wide range of geographical scales. We analysed the genome sequences and epidemiological data of >1,700 K. pneumoniae samples isolated from patients in 244 hospitals in 32 countries during the European Survey of Carbapenemase-Producing Enterobacteriaceae. We demonstrate that carbapenemase acquisi-tion is the main cause of carbapenem resistance and that it occurred across diverse phylogenetic backgrounds. However, 477 of 682 (69.9%) carbapenemase-positive isolates are concentrated in four clonal lineages, sequence types 11, 15, 101, 258/512 and their derivatives. Combined analysis of the genetic and geographic distances between isolates with different β-lactam resistance determinants suggests that the propensity of K. pneumoniae to spread in hospital environments correlates with the degree of resistance and that carbapenemase-positive isolates have the highest transmissibility. Indeed, we found that over half of the hospitals that contributed carbapenemase-positive isolates probably experienced within-hospital transmission, and interhospital spread is far more frequent within, rather than between, countries. Finally, we propose a value of 21 for the number of single nucleotide polymorphisms that optimizes the discrimination of hospital clusters and detail the international spread of the successful epidemic lineage, ST258/512.

Reference: Sophia David et al., Epidemic of carbapenem-resistant Klebsiella pneumoniae in Europe is driven by nosocomial spread, Nature Microbiology, 2019. https://doi.org/10.1038/s41564-019-0492-8. https://www.nature.com/articles/s41564-019-0492-8