The multidrug-resistant Staphylococcus capitis NRCS-A clone is responsible for sepsis in preterm infants in neonatal intensive care units (NICUs) worldwide. Here, to retrace the spread of this clone and to identify drivers of its specific success, we investigated a representative collection of 250 S. capitis isolates from adults and newborns. Bayesian analyses confirmed the spread of the NRCS-A clone and enabled us to date its emergence in the late 1960s and its expansion during the 1980s, coinciding with the establishment of NICUs and the increasing use of vancomycin in these units, respectively. This dynamic was accompanied by the acquisition of mutations in antimicrobial resistance- and bacteriocin-encoding genes. Furthermore, combined statistical tools and a genome-wide association study convergently point to vancomycin resistance as a major driver of NRCS-A success. We also identified another S. capitis subclade (alpha clade) that emerged independently, showing parallel evolution towards NICU specialization and non-susceptibility to vancomycin, indicating convergent evolution in NICU-associated pathogens. These findings illustrate how the broad use of antibiotics can repeatedly lead initially commensal drug-susceptible bacteria to evolve into multidrug-resistant clones that are able to successfully spread worldwide and become pathogenic for highly vulnerable patients.

中文翻译：

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与新生儿败血症有关的头状葡萄球菌的利基专业化和传播。

耐多药的头状葡萄球菌 NRCS-A 克隆是全球新生儿重症监护病房 (NICU) 早产儿败血症的原因。在这里，为了追溯这种克隆的传播并确定其特定成功的驱动因素，我们调查了从成人和新生儿中分离出的 250 株 S. capitis 的代表性集合。贝叶斯分析证实了 NRCS-A 克隆的传播，使我们能够确定它在 1960 年代后期的出现和在 1980 年代的扩张，这与新生儿重症监护病房的建立和这些单位中万古霉素的使用增加相吻合，分别。这种动态伴随着获得抗菌素耐药性和细菌素编码基因的突变。此外，结合统计工具和全基因组关联研究一致表明，万古霉素耐药性是 NRCS-A 成功的主要驱动力。我们还确定了另一个独立出现的 S. capitis 亚进化枝（α进化枝），显示出向 NICU 专业化和对万古霉素不敏感的平行进化，表明 NICU 相关病原体的趋同进化。这些发现说明了抗生素的广泛使用如何反复导致最初的共生药物敏感细菌演变成能够在全球范围内成功传播并成为高度易感患者致病菌的多重耐药性克隆。显示向 NICU 专业化和对万古霉素不敏感的平行进化，表明 NICU 相关病原体的趋同进化。这些发现说明了抗生素的广泛使用如何反复导致最初的共生药物敏感细菌演变成能够在全球范围内成功传播并成为高度易感患者致病菌的多重耐药性克隆。显示向 NICU 专业化和对万古霉素不敏感的平行进化，表明 NICU 相关病原体的趋同进化。这些发现说明了抗生素的广泛使用如何反复导致最初的共生药物敏感细菌演变成能够在全球范围内成功传播并成为高度易感患者致病菌的多重耐药性克隆。