The US Centers for Disease Control and Prevention (CDC) announced on Nov 19 that it was launching a task force to investigate the causes and treatment for patients with acute flaccid myelitis (AFM), a polio-like disease that affects the spinal cord causing muscle weakness and sometimes paralysis, mostly in children. Since 2014, the USA has seen an increase in the number of confirmed cases of AFM, which has no cure or vaccine. So far this year, there have been 106 confirmed cases of AFM in 29 states, all but five of which were observed in children aged 18 years or younger, the CDC said.

   The AFM task force, which is scheduled to submit its first report on Dec 6, will bring together expertsfrom a variety of scientific, medical, and public health disciplines, said Robert R Redfield, CDC director.“I want to reaffirm to parents, patients, and our nation CDC’s commitment to this serious medical condition”, he said. Clinicians who are treating children with the disease and who have urged better data collection and research have welcomed the task force. The CDC has also come under pressure from parents’ advocacy groups that have used social media to urge more outreach with hospital emergency rooms to recognise AFM symptoms, which can appear as a common cold before progressing to paralysis.“This is only the beginning of what we hope will be a more productive and engaged stance from the CDC”, Keith Van Haren, an assistant professor of neurology at the Stanford University School of Medicine, told The Lancet.

  “I’m not pursuing funding. But my colleagues and I are watching children develop permanent disabilities. We need more research and more personnel working on this.” EV-D68: an enterovirus that might be a cause Clinicians have found that a particular enterovirus, known as EV-D68, is the

most commonly identified virus with AFM. However, the CDC cautions that the cause of AFM remains unknown. Enteroviruses peak about every 2 years in the late summer and autumn in the northern hemisphere under a specific combination of humidity and temperature along with a large

enough population of susceptible hosts, such as children. Taking biopsies of the affected tissues in the brain and spine is too risky for patients so doctors have mostly analysed spinal fluid where

enteroviruses, which can move through nerves directly, do not always show up. Waves of AFM cases have been detected starting in 2012 in the USA. Several clinicians, including Kevin Messacar, an infectious disease physician at the Children’s Hospital Colorado, started searching for EV-D68 after the 2014 outbreak using nasal swabs taken from patients with generic cold symptoms. Another

enterovirus, EV-71, was also found, leading to speculation that several enteroviruses could be the cause of AFM. Messacar’s surveillance of EV-D68 meant that he saw this year’s outbreak

coming. “We were able to detect early when the pathogen was circulating and to prepare for when the calls and emails starting coming in about AFM from around the country this year”, he

told The Lancet.

“Active surveillance of EV-D68 helps in both early detection and the investigation of the causes of AFM. We need to prepare for 2020 and vaccines take time, so we need to start now.” The CDC’s surveillance programme for enteroviruses is passive and relies on clinicians sending in samples but a

more active system would require any child with respiratory problems to be tested for EV-D68.

Cases of AFM have been detected in Europe and Japan but not in the same numbers as in the USA.

Messacar has been collaborating with Hubert Niesters, director of the Laboratory of Clinical Virology

at the University Medical Centre in Groningen, Netherlands. They coauthored a study published in The Lancet Infectious Diseases in February saying that EV-D68 was the likely cause of AFM. Niesters told The Lancet that three cases were found in Europe in 2014 and 39 cases in 2016. “This year we’ve seen more cases of adults in Wales and I’m sure there are more cases in Europe although not as many as in the USA.

But the problem is we cannot get the data”, he said. Niesters and other European virologists have been pushing for greater surveillance of EV-D68 and AFM and for collaboration with clinicians. “If the CDC or WHO said we have to do it [collect data], then the money would be found”, he said.

“Polio also started as a rare disease and a vaccine is possible. If it was your child, you would do everything even if it was a rare disease.”

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)33012-5/fulltext

US CDC task force to investigate acute flaccid myelitis cases.pdf

美国患急性弛缓性脊髓炎儿童持续增加 肠道病毒被疑是罪魁祸首

2018-11-21 13:26 

【环球网综合报道】据美国“侨报纽约网”11月20日报道，美国疾病控制与预防中心(CDC)19日公布的数据显示，更多的美国儿童已经被诊断出患有急性弛缓性脊髓炎(AFM)，这是一种脊髓灰质炎样瘫痪性疾病)。

据CNN报道，CDC的数据显示，自2014年以来，全美已经有430例确诊的AFM病例，其中90%是儿童。今年，全美有29个州共106例确诊的AFM病例，本周又新增了16例。此外，还有167例疑似病例，比前一周增加了5例。

AFM是一种罕见的疾病，它会影响神经系统，尤其是脊髓灰质，导致肌肉无力和突然瘫痪。孩子们可能会受到以下的影响：有的肢体瘫痪，有的颈部以下瘫痪，只有在呼吸机的帮助下才能呼吸。此外，该病没有治愈方法，没有疫苗可以预防，且目前还未发现病源。CDC的一些神经学家表示，他们确信肠道病毒最有可能是导致小儿麻痹症的罪魁祸首，但目前并没有定论。

当被问及毒素或疫苗是否会触发AFM时，美国国家免疫与呼吸系统疾病中心主任梅索尼埃(Messonnier)回答说：“目前我们还没有排除任何可能性。”

CDC上周的报告说，在瘫痪前大约3到10天，几乎所有患有AFM的儿童都出现了病毒性疾病，症状包括发烧和咳嗽。病毒性疾病在儿童中很常见，所以目前还不清楚为什么只有相对较少的人会患上AFM。即使在同一个家庭中，几个兄弟姐妹也会出现同样的感冒症状，但只有一个会瘫痪。

在CNN 10月的一篇报道中，CDC的几名医疗顾问和患病儿童的父母批评该机构应对疫情的速度太慢。(实习编辑: 周思敏 审稿：谭利娅)

https://3w.huanqiu.com/a/c36dc8/7I0HuTVNbb2?agt=20&tt_group_id=6626182131297026567

https://www.msn.com/en-us/health/medical/cdc-sets-up-task-force-as-polio-like-condition-spreads/ar-BBPUJxc

美国新增 22 例类小儿麻痹症，疑为肠道病毒 D68（EV-D68）感染

　　10月16日美国亚特兰大疾病控制中心在新闻发布会上称，近几周已经确认22个州62例急性迟缓性脊髓炎，另外有62人正在接受排查。此次出现的急性迟缓性脊髓炎与小儿麻痹症状类似，患儿表现为肢体瘫痪、无法走路。

　　这次感染原因还不是很明确，有科学家怀疑与秋季肠道病毒D68（EV-D68）爆发感染相关。目前此疾病尚缺乏治疗与预防措施，科学家正通过动物实验研发疫苗。（来源：Science）下面我们简单认识一下D68（EV-D68）。

　　人肠道病毒D6是小RNA病毒科、肠道病毒属D组成员，于1962年美国加利福尼亚地区小儿肺炎的呼吸道标本中首次被分离鉴定，2005年以来在全球多个地区频繁暴发，引发严重的呼吸系统和中枢神经系统症状，危害公众健康。

　　根据美国国家肠道病毒监测系统的数据统计，在1970年至2005年期间只发现26例EVD68感染的病例，EVD68相关的感染一度被认为是及其罕见的 。然而从2005年开始该病毒在美国、亚洲 、欧洲等全球多个地区频繁暴发，发病率持续增高，2014年美国经历的EVD68暴发感染最为严重，期间有1153例确诊并伴随着严重呼吸系统症状的病例；许多回顾性研究证实在同时期欧洲也存在EVD68的流行感染。EVD68感染最常见的临床表现是呼吸系统症状，然而，作为一种非脊髓灰质的肠道病毒，EVD68被发现也能导致松弛性肌无力、神经功能障碍等类脊髓灰质炎（poliolike）神经症状的相关疾病，该疾病被称为急性弛缓性脊髓炎（Acute flaccid myelitis，AFM），这一临床现象提示EVD68潜在引发神经系统疾病，因此引起病毒学家们的广泛关注。

　　预防治疗

　　医学专家建议，最好的方法是预防感染，而最好的预防措施是洗手和保持清洁，避免与感染者接触。

http://www.scii.net/news_hot/856.html

Emerg Infect Dis：2014年美国爆发的急性迟缓性脊髓炎与EV-D68相关

根据CDC最近的发现指出，在2014年美国科罗拉多爆发的一系列病例中，患有急性迟缓性脊髓炎的儿童有10倍的风险感染D68肠病毒。

2014年8月8日到2014年10月14日，科罗拉多儿童医院涌现了一批出现急性肢体无力、颅神经功能障碍，有典型临床症状和影像学发现脊髓炎的患儿，CDC流行病情报服务部分的官员Negar Aliabadi博士写到，"尽管没有发现这类患者存在神经系统疾病的病因，但在45%的患者鼻咽部发现了EV-D68病毒。"

来自CDC、科罗拉多大学和儿童医院的研究人员对在本医院或邻近机构接受过呼吸系统疾病治疗的儿童 (n = 11)进行了一项回顾性病例对照研究。他们收集了鼻咽部的样本进行病原学检测，历时2个月发现了不同上呼吸道疾病与出现EV-D68的关系。

Aliabadi和同事建立了两个对照组：第一组包含门诊治疗儿童，使用多重呼吸道病原体荧光PCR(RPP-PCR)检测鼻咽部样本。第二组包含门诊患者，使用PCR检测鼻咽部样本查找百日咳杆菌。病例中患者年龄小于21岁，考虑为急性延缓性脊髓炎需有急性神经系统疾病，MRI发现脊髓磁共振病变，无可识别的病因和局部肢体无力。

研究人员检测了两个模型比较急性延缓性脊髓炎和对照组。第一个模型检测了 EV-D68与急性延缓性脊髓炎的关系，第二个模型检测了肠病毒和鼻病毒的关系。

在203份来自ICU和急性延缓性脊髓炎患者的标本中，Aliabadi 和同事识别了49%的EV-D68阳性。除此之外，在流行病期间，科罗拉多儿童医院急性延缓性脊髓炎诊断高峰与EV-D68呼吸道感染同事出现。在肠道病毒和鼻病毒样本中未检测到主要病毒。

在爆发期间，研究人员认定的13例患有急性延缓性脊髓炎出现了肢体无力和/或颅神经障碍。2人未出现肢体无力，排除在研究之外。急性延缓性脊髓炎患者比RPP检测对照组的年龄要大(P=.05)，比检测百日咳杆菌组发热程度要高(P < .001)。

Aliabadi和研究人员说道，"这些流行病学数据，结合生物学原因，揭示了疾病可能的关联；但流行病学数据与进一步的实验室样本检测数据之间仍存在差距。"Kate Sherrer写到，"提高对急性延缓性脊髓炎的监控，及时全面的收集样本并检测EV-D68病毒是有必要的。"

原始出处：

EV-D68, acute flaccid myelitis linked during 2014 Colorado outbreak，healio,July 22, 2016

Aliabadi N, et al. Enterovirus D68 Infection in Children with Acute Flaccid Myelitis, Colorado, USA, 2014,Emerg Infect Dis. 2016;doi:10.3201/eid2208.