Oxford University Clinical Research Unit, Patan Academy of Health Sciences, Satdobato, Lagankhel Rd, Patan, Kathmandu, Nepal.
Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, 764 Vo Van Kiet Street, Quan 5, Ho Chi Minh City, Vietnam.
Trans R Soc Trop Med Hyg. 2018 Oct 1;112(10):467-472. doi: 10.1093/trstmh/try077.
Human infections with Serratia spp. are generally limited to Serratia marcescens and the Serratia liquefaciens complex. There is little data regarding the infections caused by the remaining Serratia spp., as they are seldom isolated from clinical specimens.
In this health care setting in Kathmandu, Nepal routine blood culture is performed on all febrile patients with a temperature >38°C or when there is clinical suspicion of bacteremia. During 2015 we atypically isolated and identified several Serratia spp. We extracted clinical data from these cases and performed whole genome sequencing on all isolates using a MiSeq system (Ilumina, San Diego, CA, USA).
Between June and November 2015, we identified eight patients with suspected bacteremia that produced a positive blood culture for Serratia spp., six Serratia rubidaea and five Serratia marcescens. The S. rubidaea were isolated from three neonates and were concentrated in the neonatal intensive care unit between June and July 2015. All patients were severely ill and one patient died. Whole genome sequencing confirmed that six Nepalese S. rubidaea sequences were identical and indicative of a single-source outbreak.
Despite extensive screening we were unable to identify the source of the outbreak, but the inferred timeline suggested that these atypical infections were associated with the aftermath of two massive earthquakes. We speculate that deficits in hygienic behavior, combined with a lack of standard infection control, in the post-earthquake emergency situation contributed to these unusual Serratia spp. outbreaks.
人类感染沙雷氏菌属通常仅限于粘质沙雷氏菌和液化沙雷氏菌复合体。由于其他沙雷氏菌属很少从临床标本中分离出来，因此有关它们引起的感染的数据很少。
在尼泊尔加德满都的这个医疗保健环境中，对所有发热患者（体温>38°C 或有菌血症临床怀疑时）进行常规血培养。在 2015 年，我们异常地分离并鉴定了几种沙雷氏菌属。我们从这些病例中提取了临床数据，并使用 MiSeq 系统（Illumina，圣地亚哥，CA，美国）对所有分离株进行全基因组测序。
在 2015 年 6 月至 11 月期间，我们确定了 8 名疑似菌血症患者，他们的血液培养物呈沙雷氏菌属阳性，其中 6 名是粘质沙雷氏菌，5 名是粘质沙雷氏菌。粘质沙雷氏菌从 3 名新生儿中分离出来，并集中在 2015 年 6 月至 7 月的新生儿重症监护病房。所有患者均病情严重，1 名患者死亡。全基因组测序证实，6 个尼泊尔粘质沙雷氏菌序列完全相同，表明这是单一来源的暴发。
尽管进行了广泛的筛查，但我们仍无法确定暴发的源头，但推断的时间线表明，这些非典型感染与两次大地震的余波有关。我们推测，在地震后的紧急情况下，卫生行为的缺陷，加上缺乏标准的感染控制，导致了这些不寻常的沙雷氏菌属暴发。
