Background In recent years, we have witnessed an unprecedented increase in the incidence of vibriosis due to global warming. Vibrio metoecus is a recently described V. cholerae-like species that has not been associated with septicemia death in humans. During follow-up of human vibriosis, we received a blood isolate from a patient with secondary septicemia who died a few hours after admission. Methods Phenotypic and genotypic methods failed to identify the isolate, which could only be identified by Average Nucleotide Identity after genome sequencing. The isolate was then subjected to a series of in vitro and ex vivo assays, complemented by comparative genomics focused on the identification of unique genetic traits. Strains and genomes from the same and related species (V. cholerae and V. mimicus) were used for analyses. Results The isolate was the only one able to resist and multiply in human serum. Its genome contained virulence genes shared with V. mimicus and/or V. cholerae, with those associated with sialic acid degradation within pathogenicity island 2 standing out. However, it also presented a unique gene cluster, flanked by a transposase gene, putatively related to surface polysaccharide pseudosialyzation. Conclusion In this study, we document the first case of death from septicemia due to V. metoecus and propose that the acquisition of surface pseudosialyzation genes would explain the ability of certain isolates of this species to survive in blood. Consequently, our discovery underscores the urgent need to monitor and study new emerging pathogenic species, as climate change may be facilitating their spread and increasing the risk of serious infections in humans.

中文翻译：

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由 Vibrio metoecus 引起的致命败血症病例的首次报告：一项全面的功能和基因组研究


背景 近年来，我们目睹了全球变暖导致的弧菌病发病率空前增加。弧菌是最近描述的一种类似霍乱弧菌的物种，与人类败血症死亡无关。在人类弧菌病随访期间，我们收到了一名继发性败血症患者的血液分离物，该患者在入院后数小时死亡。方法 表型和基因型方法无法鉴定分离株，只能通过基因组测序后的平均核苷酸鉴定来鉴定。然后对分离物进行一系列体外和离体测定，并辅以专注于鉴定独特遗传性状的比较基因组学。使用来自相同和相关物种 （V. cholerae 和 V. mimicus） 的菌株和基因组进行分析。结果 该分离株是人血清中唯一能够抵抗和繁殖的分离株。其基因组包含与拟弧菌和/或霍乱弧菌共有的毒力基因，其中与致病性岛 2 内的唾液酸降解相关的基因脱颖而出。然而，它也呈现出一个独特的基因簇，两侧是转座酶基因，推测与表面多糖假唾液酸解有关。结论 在这项研究中，我们记录了第一例因 V. metoecus 引起的败血症死亡，并提出获得表面假唾液酸解基因将解释该物种的某些分离株在血液中存活的能力。因此，我们的发现强调了监测和研究新出现的病原物种的迫切需要，因为气候变化可能正在促进它们的传播并增加人类严重感染的风险。