原标题：外媒：参与武汉病毒研究所工作的美专家表示“实验室泄露极其不可能”
美媒《商业内幕》当地时间2日报道称，曾对武汉病毒研究所人员进行培训并参与相关合作的加利福尼亚大学戴维斯分校流行病专家乔娜·马泽特（Jonna Mazet）认为，新冠病毒的暴发极不可能源自实验室泄露，主要有如下四个原因。
The start of COVID-19 pandemic is“highly unlikely a lab accident，” Jonna Mazet， an epidemiologist at the University of California， Davis， who has worked with and trained researchers from Wuhan Institute of Virology in the past told Business Insider。 Here are four reasons why。
其一，实验室样品与新冠病毒不匹配。武汉病毒研究所专家石正丽团队在对新冠病毒进行基因测序后，迅速检查了过去几年研究所记录，结果显示新冠病毒基因组与实验室样品（其他蝙蝠冠状病毒）并不匹配。马泽特称自己与石正丽近期有过交谈，石正丽肯定自己在疫情暴发之前从未鉴定出这种病毒。
Reason 1： The lab‘s samples don’t match the new coronavirus
The WIV houses China‘s only Biosafety-level-4 laboratory。 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。。。 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 hadcollected。They didn‘t match。Mazet has met and worked with Shi through PREDICT， a pandemic early-warning program started by the US Agency for International Development。“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。”
其二，实验室执行严格的安全协议。马泽特介绍称，从蝙蝠身上收集的样本会立即被分装至化学瓶中，并当场被浸入液氮里冷冻，经消毒后运往实验室，再由研究人员装至零下80摄氏度的冰箱里。研究人员都穿戴多层手套、护目镜、全身防护服和口罩等个人防护装备。马泽特表示，武汉实验室的现场工作无可指摘。
Reason 2： The lab implements rigorous safety protocols
。。。 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。 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。
其三，新冠病毒是人畜共患疾病中暴发的最新一例病毒。报道表示，每四个新出现的传染病中有三个都来自其他物种，新冠病毒是自上个世纪以来，传给人类的第七种人畜共患病毒。因此，新冠病毒更有可能是从动物宿主传播到人类身上的，埃博拉和“非典”就是这样暴发的。
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。。。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。
最后，普通人比研究人员更容易接触感染活体病毒。马泽特表示，野生蝙蝠生活的洞穴和野外栖息地十分危险，武汉实验室研究人员在穿越洞穴时穿戴完备的个人防护设备。相比之下，游客、偷猎者等普通人群更有接触动物活体病毒的可能，因此风险更大。马泽特还认为，“实验室泄露”的说法或会侵蚀中美研究员之间的信任，影响科学合作。
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。
（Source： Business Insider）
