PDF(Pubmed)
Abstract：
The majority of Kenya’s > 3 million camels have antibodies against Middle East respiratory syndrome coronavirus (MERS-CoV), although human infection in Africa is rare. We enrolled 243 camels aged 0−24 months from 33 homesteads in Northern Kenya and followed them between April 2018 to March 2020. We collected and tested camel nasal swabs for MERS-CoV RNA by RT-PCR followed by virus isolation and whole genome sequencing of positive samples. We also documented illnesses (respiratory or other) among the camels. Human camel handlers were also swabbed, screened for respiratory signs, and samples were tested for MERS-CoV by RT-PCR. We recorded 68 illnesses among 58 camels, of which 76.5% (52/68) were respiratory signs and the majority of illnesses (73.5% or 50/68) were recorded in 2019. Overall, 124/4692 (2.6%) camel swabs collected from 83 (34.2%) calves in 15 (45.5%) homesteads between April−September 2019 screened positive, while 22 calves (26.5%) recorded reinfections (second positive swab following ≥ 2 consecutive negative tests). Sequencing revealed a distinct Clade C2 virus that lacked the signature ORF4b deletions of other Clade C viruses. Three previously reported human PCR positive cases clustered with the camel infections in time and place, strongly suggesting sporadic transmission to humans during intense camel outbreaks in Northern Kenya.
摘要：
肯尼亚300万头骆驼中的大多数都有针对中东呼吸综合征冠状病毒（MERS-CoV）的抗体，虽然人类感染在非洲是罕见的。我们从肯尼亚北部的33个家庭中招募了243只0-24个月大的骆驼，并在2018年4月至2020年3月期间对它们进行了跟踪。我们通过RT-PCR收集并测试骆驼鼻拭子的MERS-CoVRNA，然后进行病毒分离和阳性样品的全基因组测序。我们还记录了骆驼中的疾病（呼吸道或其他）。人类骆驼工人也被擦拭，筛查呼吸体征，并通过RT-PCR检测样品的MERS-CoV。我们记录了58只骆驼中的68种疾病，其中76.5%(52/68)是呼吸体征，大多数疾病(73.5%或50/68)是在2019年记录的。总的来说,在2019年4月至9月之间，从15个（45.5％）宅基地的83只（34.2％）小牛中收集的124/4692只（2.6％）骆驼拭子呈阳性，而22只小牛（26.5％）记录了再感染（连续2次阴性测试后第二次阳性拭子）。测序揭示了一种独特的分化体C2病毒,其缺乏其他分化体C病毒的特征ORF4b缺失。先前报道的三例人类PCR阳性病例在时间和地点与骆驼感染聚集在一起，强烈暗示在肯尼亚北部强烈的骆驼暴发期间零星传播给人类。
