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家园 石说了,武汉所的病毒和新冠的基因序列不匹配。

原文是“Did NOT match"

下面使用百度译的

https://www.businessinsider.com/why-coronavirus-did-not-leak-from-wuhan-lab-researcher-2020-4

一位在武汉病毒学实验室工作的美国研究员给出了冠状病毒泄露可能性极小的四个原因

Aylin Woodward

5/2/2020

一种边缘理论认为,冠状病毒可能是从中国武汉病毒学研究所的实验室泄漏的,但没有证据表明这一点。

一位曾在武汉实验室与科学家合作的美国研究员向商业内幕人士解释了为什么实验室意外泄漏的可能性性极小。

高级安全实验室说,它没有新冠状病毒基因组的记录,并遵循严格的安全措施。

更可能的是病毒从蝙蝠身上自然传出,通过中间的动物宿主跳到人类身上。

武汉病毒学研究所(WIV)的研究人员对包括冠状病毒在内的传染病进行研究,并在新冠大流行开始前就做这类研究。因此,随着没人能回答这次大流行是如何开始的问题,这个实验室引起了人们的注意。

据《纽约时报》报道,特朗普的国家安全副顾问马修·波廷格(Matthew Pottinger)今年1月要求情报机构调查武汉实验室泄露的想法。但中情局官员没有找到任何证据。

加州大学戴维斯分校的流行病学家Jonna Mazet说,这是有原因的,他过去曾与WIV研究人员合作并受过培训。

她对《商业内幕》说:“我知道,我们共同制定了非常严格的安全规程,这个疫情极其不可能是实验室事故。”。原因有四个。

原因一:实验室的样本与新型冠状病毒不匹配

WIV拥有中国唯一的生物安全四级实验室,是世界上仅有的十几个实验室之一。科学家们在这些设施中研究人类已知的最危险和最具传染性的微生物。该研究所的一些研究人员,包括病毒学家施正礼,已经收集、取样并研究了传播中国蝙蝠的冠状病毒。2013年,石正丽和她的合作者在昆明附近的石头洞发现了最有可能传播非典的蝙蝠种群。

在她的团队对COVID-19病毒进行测序后,Shi告诉《科学美国人》,她很快检查了实验室过去几年的记录,以检查是否有事故,特别是在处理过程中。然后她将新的冠状病毒基因组与她团队收集到的其他蝙蝠冠状病毒的基因信息交叉引用。他们不匹配。

“这真的让我松了一口气,”石正丽对《科学美国人》杂志说,“我已经好几天没合眼了。”

马泽特通过美国国际开发署(usagencyforinternationaldevelopment)启动的流行病预警项目PREDICT与Shi进行了会晤和合作。该项目已经在包括WIV在内的30个国家培训了员工并资助了实验室,但据唐纳德·特朗普总统去年秋天预测,该项目已经关闭。

“我最近和她谈过了,”马泽特说她绝对肯定,在疫情爆发之前,她从未发现过这种病毒。”

马泽特补充说,石正丽建立了一个安全、共享的数据库,预测成员可以将他们的作品上传到其中公开发布。

原因二:实验室实施严格的安全规程

《华盛顿邮报》获得的外交电文显示,2018年,美国官员对WIV的安全问题表示担忧。但马泽特说,石正丽在实验室和实地的工作无可厚非

她说:“在野外,他们会穿戴极端的个人防护装备,包括多层手套、护目镜、全身防护服和口罩。”。(然而,她指出,她并没有亲自访问过WIV,也无法对所有在那里进行的研究发表意见。)马泽特补充说,从蝙蝠身上采集的样本,会立即分装在一些装有使病毒失效的化学物质的小瓶和其他使病毒存活的容器中。

然后,所有的样品都在现场浸泡在液氮中,液氮将其冷冻,然后对小瓶进行消毒并运送到实验室。在那里,科学家们穿着个人防护装备(PPE)将其卸入设置在零下80摄氏度的冰柜中。

马泽特说,当稍后研究这些样本时,研究人员只使用失活的、非传染性的样本,并补充说,带有活病毒的小瓶被锁定在一个特殊区域。

原因三:冠状病毒是一长串人畜共患疾病爆发的最新病毒

专家说,冠状病毒更可能是最新的一种从动物宿主跳到人类身上的疾病,而不是一个漏洞。

这种被称为溢出事件的跨物种跳跃也导致了埃博拉和非典的爆发。这两种病毒都起源于蝙蝠,基因研究几乎证实了这种新型冠状病毒的相同之处——今年2月发表的一项研究发现,这种病毒与在中国蝙蝠种群中传播的冠状病毒共享96%的基因代码。

每四种新出现的传染病中就有三种来自其他物种;这些病原体被称为人畜共患病。冠状病毒是上个世纪第七种传染给人类的人畜共患病病毒。

2009-2010年的H1N1大流行-猪流感-开始于猪,然后杀死了近30万人。人们通过直接接触受感染的家禽而感染禽流感。其他流感大流行,包括1957“亚洲流感”和1968香港大流行,也可能从鸟类中开始。

在过去的45年里,至少有4起流行病可以追溯到蝙蝠。

原因四:日常生活中的人比穿防护服的研究人员更容易被感染

马泽特说,从蝙蝠身上采集样本的洞穴和野生栖息地对人类来说是危险的地方,因为人类可能接触到动物体内传播的活病毒。

石正丽的研究人员带着全套个人防护装备在这些洞穴中航行;但游客、猎人、偷猎者和其他以某种能力依赖动物为食或贸易的人,则会游荡到这些保护较少的地方。

生态健康联盟(EcoHealth Alliance)主席彼得•达扎克(Peter Daszak)上周对美国国家公共电台(NPR)表示,他的同事每年在东南亚“发现100万至700万人接触”人畜共患病病毒。

“这就是途径。这对我们所有在实地工作的人来说都是显而易见的。”。

2019年3月发表的一项研究甚至预测,蝙蝠将成为中国新一轮冠状病毒爆发的源头。作者说,这是因为大多数冠状病毒——影响人类和动物的冠状病毒——都可以在中国发现,许多蝙蝠“生活在中国人类附近,有可能将病毒传播给人类和牲畜”。

溢出效应将继续发生

马泽特说,随着人类进一步侵入野生栖息地,外溢事件的频率将增加,这些野生栖息地容纳了我们以前从未接触过的携带疾病的物种。研究过去的溢出是如何发生的,以及哪些栖息地是此类事件的最大风险,有助于科学家对下一次大流行做出预测。

自2014年以来,石正丽在WIV的团队从国家变态反应和传染病研究所(National Institute of Allergy and Infectional Diseases)资助的数百万美元的五年期赠款中获得了近60万美元,用于研究蝙蝠冠状病毒的外溢。这项由生态健康联盟(EcoHealth Alliance)管理的拨款在2019年又延长了5年。

不过,特朗普总统在4月17日的白宫简报会上被问及这笔资金后表示,他的政府将“非常迅速地结束这笔拨款”

一周后,美国国立卫生研究院取消了这项计划。

削弱我们和中国研究人员之间的信任

WIV生物安全实验室主任袁志明对路透社表示,有关该实验室的“恶意”说法是“凭空提出的”,与所有现有证据相矛盾。

马泽特认为,实验室泄漏理论的持续流传可能会影响美中两国未来的科学合作和信息共享。

“现在社会学上发生的事情是我们最大的风险——如果他们是被放在显微镜下的人,谁会想去研究这个?”马泽特说马泽特说:“我认为,现在发生的事情的真正危险在于,由于政府的压力,像施和我这样的专家可能无法继续合作识别这些病毒。”。

这将使人们更难发现COVID-19病毒的来源,也更难预测和准备下一次的外溢。

马泽特补充说,她担心一场指责游戏甚至会在短期内危及生命。

“如果我们把矛头指向那些有最好机会开发疫苗的国家,为什么我们希望他们能自由地与我们分享?”马泽特说现在,合作是关键,否则你就让各国并行发展,你不能想当然地认为美国在所有方面都是最好的。”

A US researcher who worked with a Wuhan virology lab gives 4 reasons why a coronavirus leak would be extremely unlikely

Aylin Woodward

5/2/2020

https://www.businessinsider.com/why-coronavirus-did-not-leak-from-wuhan-lab-researcher-2020-4

A fringe theory suggests the coronavirus could have leaked from a lab at the Wuhan Institute of Virology in China, but there's no evidence of this.

One US researcher who has worked with scientists at that Wuhan lab explained to Business Insider why an accidental lab leak is extremely unlikely.

The high-security lab says it has no record of the novel coronavirus' genome, and follows strict safety measures.

It's far more likely that the virus spilled over naturally from bats, jumping to humans via an intermediary animal host.

Researchers at the Wuhan Institute of Virology (WIV) study infectious diseases, including coronaviruses, and did before the pandemic started. So as questions about how the pandemic started continue to go unanswered, the lab has drawn scrutiny.

Matthew Pottinger, Trump's deputy national security adviser, asked intelligence agencies in January to look into the idea of a Wuhan lab leak, The New York Times reported. But CIA officers didn't find any evidence.

There's a reason for that, according to Jonna Mazet, an epidemiologist at the University of California, Davis, who has worked with and trained WIV researchers in the past.

"I know that we worked together to develop very stringent safety protocol, and it's highly unlikely this was a lab accident," she told Business Insider. Here are four reasons why.

Reason 1: The lab's samples don't match the new coronavirus

The WIV houses China's only Biosafety-level-4 laboratory, which is one of only a dozen in the world. Scientists study the most dangerous and infectious microbes known to humankind in these types of facilities. Some of the institute's researchers, including virologist Shi Zhengli, have collected, sampled, and studied coronaviruses that circulate Chinese bats. In 2013, Shi and her collaborators pinpointed the bat population most likely responsible for spreading SARS, in the Shitou Cave near Kunming.

After her team sequenced the COVID-19 virus, Shi told Scientific American that she quickly checked her laboratory's record from the past few years to check for accidents, especially during disposal. Then she cross-referenced the new coronavirus' genome with the genetic information of other bat coronaviruses her team had collected. They didn't match.

"That really took a load off my mind," Shi said told Scientific American, adding, "I had not slept a wink for days."

Mazet has met and worked with Shi through PREDICT, a pandemic early-warning program started by the US Agency for International Development. The program has trained staff and funded labs in 30 countries, including the WIV, but President Donald Trump shut down PREDICT last fall.

"I've spoken to her recently," Mazet said of Shi. "She is absolutely positive that she had never identified this virus prior to the outbreak happening."

Mazet added that Shi set up a secure, shared database into which PREDICT members could upload their work for public release.

Reason 2: The lab implements rigorous safety protocols

In 2018, US officials raised concerns about safety issues at WIV, according to diplomatic cables obtained by The Washington Post. But Mazet said Shi's work in the lab and in the field was above reproach.

"In the field, they wear extreme personal protective equipment, including multiple layers of gloves, eye protection, full body suits, and masks," she said. (She noted, however, that she has not personally visited the WIV and couldn't speak to all the research done there.) Samples collected from bats, Mazet added, get immediately split between some vials that contain chemicals that deactivate the virus, and other containers that leave the virus alive.

All samples are then dunked into liquid nitrogen on the spot, which freezes them, then the vials are disinfected and transported to the lab. There, scientists wearing personal protective equipment (PPE) unload them into a freezer set to minus 80 degrees Celsius.

When the samples are studied later, researchers only use the deactivated, non-infectious ones, Mazet said, adding that the vials with viable virus are locked down in a special area.

Reason 3: The coronavirus is the latest in a long line of zoonotic disease outbreaks

Rather than a leak, the coronavirus is more likely the latest disease to have jumped from an animal host to humans, experts say.

This type of cross-species hop, called a spillover event, also led to outbreaks of Ebola and SARS. Both of those viruses originated in bats, and genetic research has all but confirmed the same for the new coronavirus — a study published in February found that it shares 96% of its genetic code with coronaviruses circulating in Chinese bat populations.

Three out of every four emerging infectious diseases come to us from other species; these pathogens are known as zoonotic diseases. The coronavirus is the seventh zoonotic virus to have spilled over into people in the last century.

The 2009-2010 H1N1 pandemic — swine flu — started in pigs then killed nearly 300,000 people. People have caught bird flus via direct contact with infected poultry. Other pandemic influenza strains, including the 1957 "Asian flu" and the 1968 Hong Kong pandemic, likely started in birds, too.

And in the last 45 years, at least four epidemics have been traced back to bats.

Reason 4: Everyday people are more likely to get infected than researchers who wear protection

The caves and wild habitats in which samples get collected from bats are dangerous places for people, since humans can be exposed to the live viruses circulating in the animals, Mazet said.

Shi's researchers navigate those caves in full PPE; but tourists, hunters, poachers, and other people who rely on animals in some capacity for food or trade wander into such places less protected.

Peter Daszak, president of EcoHealth Alliance (which managed PREDICT's relationship with the WIV), told NPR last week that his colleagues are "finding 1 to 7 million people exposed" to zoonotic viruses in Southeast Asia each year.

"That's the pathway. It's just so obvious to all of us working in the field," he said.

A study published in March 2019 even predicted that bats would be the source of a new coronavirus outbreak in China. That's because the majority of coronaviruses — those that affect humans and animals — can be found in China, and many bats "live near humans in China, potentially transmitting viruses to humans and livestock," the authors said.

Spillovers will keep happening

The frequency of spillover events will increase as humans encroach further into wild habitats that house disease-carrying species we haven't interacted with before, Mazet said. Researching how past spillovers happened and which habitats present the greatest risk for such events helps scientists make predictions about the next pandemic.

Since 2014, Shi's group at the WIV has received nearly $600,000 from a multi-million dollar, five-year grant funded by the National Institute of Allergy and Infectious Diseases to research the spillover of bat coronaviruses. The grant, which is managed by EcoHealth Alliance, was renewed for another five years in 2019.

However, after being questioned about that funding at a White House briefing on April 17, President Trump said his administration would "end that grant very quickly."

A week later, the National Institutes of Health canceled it.

Eroding confidence between US and Chinese researchers

Yuan Zhiming, director of the WIV's biosafety laboratory, told Reuters that "malicious" claims about the lab had been "pulled out of thin air" and contradicted all available evidence.

The persistent circulation of the lab-leak theory could impact future scientific cooperation and information sharing between the US and China, according to Mazet.

"What's happening sociologically right now is our biggest risk —who's going to want to work on this if they're the ones put under a microscope?" Mazet said. "I think the real danger of what's going on now is that experts like Shi and myself may not be able to keep collaborating to identify these viruses because of government pressures." Mazet said.

That would make it harder to discover where the COVID-19 virus came from, as well as to forecast and prepare for the next spillover.

Mazet added that she worries a blame game could even put lives at risk in the short term.

"If we point fingers at other nations that have best opportunity to develop a vaccine, why would we expect them to freely share that with us?" Mazet said. "Collaboration is key right now, otherwise you have countries developing things in parallel, and you can't assume the US is the best at everything."

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