Background

Bacillus cereus is a well-known pathogen for self-limited foodborne illness, and rarely an opportunistic pathogen associated with invasive infections among immunocompromised patients. Nosocomial outbreaks have been rarely reported.

Methods

Between August and November 2019, four preterm neonates in neonatal care units of a medical center developed late-onset B. cereus bacteremia. An investigation was carried out. Forty-eight environmental specimens were obtained from these neonatal units, skin surface and environmental objects of Patient 4 for the detection of this organism 19 days after the onset of illness of Patient 4. B. cereus isolates from Patient 4, five unrelated patients and environmental objects if identified were further characterized by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST).

Results

All four infants survived after vancomycin-containing treatment. Patient 4 developed diffuse cerebritis, brain abscess with severe neurologic sequelae. Of the 48 environmental samplings, 26 specimens showed positive for B. cereus, with one major clone (sequence type 365) accounting for 73%. The isolate from Patient 4 (ST427) was identical to one isolate collected from environmental objects in the same unit. After extensive cleaning of the environment and re-institution of the sterilization procedure of hospital linens, which was ceased since two months before the outbreak, no more cases was identified in these units for at least one year.

Conclusions

We documented a cluster of B. cereus bacteremia involving four preterm infants, which might be associated with cessation of the procedure for linen sterilization and was successfully controlled by re-institution of this procedure.

中文翻译：

---

新生儿护理单位一簇蜡状芽孢杆菌菌血症的调查

背景

蜡状芽孢杆菌是一种众所周知的自限性食源性疾病病原体，在免疫功能低下的患者中很少是与侵袭性感染相关的机会性病原体。很少有医院内暴发的报道。

方法

2019 年 8 月至 2019 年 11 月，一家医疗中心新生儿护理室的四名早产儿出现迟发性蜡状芽孢杆菌菌血症。进行了调查。在患者 4 发病 19 天后，从患者 4 的这些新生儿单元、皮肤表面和环境物体中获取了 48 个环境样本，用于检测该生物体。从患者 4、5 名无关患者和环境中分离出蜡状芽孢杆菌。如果识别出的对象，则通过脉冲场凝胶电泳 (PFGE) 和多位点序列分型 (MLST) 进一步表征。

结果

所有四名婴儿在含万古霉素的治疗后都存活了下来。患者 4 出现弥漫性脑炎、脑脓肿和严重的神经系统后遗症。在48份环境样本中，26份标本呈蜡状芽孢杆菌阳性，其中1个主要克隆（序列类型365）占73%。来自患者 4 (ST427) 的分离物与从同一单位的环境对象中收集的一种分离物相同。在对环境进行大范围清洁并重新实施自疫情爆发前两个月以来停止的医院布草消毒程序后，这些单位至少一年内没有发现更多病例。

结论

我们记录了一组涉及四名早产儿的蜡状芽孢杆菌菌血症，这可能与停止亚麻消毒程序有关，并通过重新实施该程序成功控制。