背景:2015年在约旦爆发的中东呼吸综合征冠状病毒(MERS-CoV)涉及一种变异病毒,该病毒在附件开放阅读框中获得了独特的缺失。我们进行了分子和血清流行病学调查,以描述缺失变体的传播模式和流行病学。
方法:我们回顾了流行病学和医学图表数据,并分析了MERS-CoV病例呼吸道标本的病毒基因组序列。2016年初,从MERS-CoV病例及其接触者获得血清和标准化访谈。通过核衣壳和刺突蛋白酶免疫测定和微中和来评估血清。
结果:16例,11人(69%)有健康护理暴露,5人(31%)是已知病例的亲属;13人(81%)有症状,7人(44%)死亡。来自13例病例的MERS-CoV的基因组测序显示,在爆发期间与临床疾病相关的3个传染性缺失。缺失变异序列在流行病学上聚集并与共同的传播链相关联。收集2例幸存病例的访谈和血清,23个家庭联系人,和278名卫生保健接触者;1例(50%),2(9%)家庭联系人,3名(1%)卫生保健接触者检测血清呈阳性。
结论:MERS-CoV缺失变体保留了人与人之间的传播性,尽管积累了突变,但仍在感染者中引起临床疾病。血清学表明,传播范围有限,超出了最初爆发调查期间发现的范围。
BACKGROUND: An outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) in Jordan in 2015 involved a variant virus that acquired distinctive deletions in the accessory open reading frames. We conducted a molecular and seroepidemiologic investigation to describe the deletion variant\'s transmission patterns and epidemiology.
METHODS: We reviewed epidemiologic and medical chart data and analyzed viral genome sequences from respiratory specimens of MERS-CoV cases. In early 2016, sera and standardized interviews were obtained from MERS-CoV cases and their contacts. Sera were evaluated by nucleocapsid and spike protein enzyme immunoassays and microneutralization.
RESULTS: Among 16 cases, 11 (69%) had health care exposure and 5 (31%) were relatives of a known case; 13 (81%) were symptomatic, and 7 (44%) died. Genome sequencing of MERS-CoV from 13 cases revealed 3 transmissible deletions associated with clinical illness during the outbreak. Deletion variant sequences were epidemiologically clustered and linked to a common transmission chain. Interviews and sera were collected from 2 surviving cases, 23 household contacts, and 278 health care contacts; 1 (50%) case, 2 (9%) household contacts, and 3 (1%) health care contacts tested seropositive.
CONCLUSIONS: The MERS-CoV deletion variants retained human-to-human transmissibility and caused clinical illness in infected persons despite accumulated mutations. Serology suggested limited transmission beyond that detected during the initial outbreak investigation.