The Klebsiella pneumoniae complex comprises seven K. pneumoniae-related species, including K. variicola. K. variicola is a versatile bacterium capable of colonizing different hosts such as plants, humans, insects and animals. Currently, K. variicola is gaining recognition as a cause of several human infections; nevertheless, its virulence profile is not fully characterized. The clinical significance of K. variicola infection is hidden by imprecise detection methods that underestimate its real prevalence; however, several methods have been developed to correctly identify this species. Recent studies of carbapenemase-producing and colistin-resistant strains demonstrate a potential reservoir of multidrug-resistant genes. This finding presents an imminent scenario for spreading antimicrobial resistant genes among close relatives and, more concerningly, in clinical and environmental settings. Since K. variicola was identified as a novel bacterial species, different research groups have contributed findings elucidating this pathogen; however, important details about its epidemiology, pathogenesis and ecology are still missing. This review highlights the most significant aspects of K. variicola, discussing its different phenotypes, mechanisms of resistance, and virulence traits, as well as the types of infections associated with this pathogen.

中文翻译：

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水痘克雷伯菌：一种在人类中出现的病原体。

肺炎克雷伯氏菌复合体包含七个与肺炎克雷伯菌有关的物种，包括水痘克雷伯菌。水痘K. variicola是一种多功能细菌，能够定植于不同的宿主，例如植物，人类，昆虫和动物。目前，水痘K.作为几种人类感染的病因而得到了认可。但是，其毒力特征尚未完全表征。水曲霉感染的临床意义被低估其真实患病率的不精确检测方法所掩盖。但是，已经开发了几种方法来正确识别该物种。产生碳青霉烯酶和大肠粘菌素抗性菌株的最新研究表明，可能具有多重抗药性基因。这一发现提出了在近亲中传播抗菌素耐药基因的迫在眉睫的计划，更重要的是，在临床和环境中。自从水曲霉被鉴定为一种新型细菌以来，不同的研究小组为阐明这种病原体做出了贡献。然而，有关其流行病学，发病机理和生态学的重要细节仍然缺失。这篇综述突出了水曲霉的最重要方面，讨论了其不同的表型，耐药性和毒力性状，以及与该病原体相关的感染类型。