During the first year of the COVID-19 pandemic, the “lab leak” theory gained little traction. Sure, U.S. President Donald Trump suggested SARS-CoV-2 originated in a laboratory in Wuhan, China—and called it “the China virus”—but he never presented evidence, and few in the scientific community took him seriously.

在2019冠狀病毒症(COVID-19：Coronavirus Disease-19)大流行的第一年，“實驗室外洩”理論鮮少獲得吸引力。當然，美國總統唐納德·川普暗示，第二型嚴重急性呼吸系統徵候群-冠狀病毒(SARS-CoV-2：Severe Acute Respiratory Syndrome Coronavirus-2)起源於中國武漢市的實驗室，且稱它為“中國病毒”。不過，他從未提出證據。因此，科學界很少人當真地受他影響。

In fact, early in the pandemic, a group of prominent researchers dismissed lab-origin notions as “conspiracy theories” in a letter in The Lancet. A report from a World Health Organization (WHO) “joint mission,” which sent a scientific team to China in January to explore possible origins with Chinese colleagues, described a lab accident as “extremely unlikely.”

事實上，在該大流行病初期，一群著名的研究人員，在給英國《柳葉刀》期刊的一封信中，將實驗室起源的概念斥為“陰謀論”。來自世界衛生組織(WHO)一項“聯合任務”，於2021年1月派遣一支科學團隊前往中國，與中國同僚們探索可能起源的一份報告，將實驗室意外事件記述為“極度不可能”。

But this spring, views began to shift. Suddenly it seemed that the lab-leak hypothesis had been too blithely dismissed. In a widely read piece, fueled by a “smoking gun” quote from a Nobel laureate, a veteran science journalist accused scientists and the mainstream media of ignoring “substantial evidence” for the scenario.

不過，今年(2021年)春天，見解開始轉變。突然間，實驗室外洩的假設，似乎已經太輕率地被拋棄。在一篇，由引述自一名諾貝爾獎得主，一項“確鑿證據”所激起，被廣泛閱讀的文章中，一位資深科學記者指責了，忽視此腳本之“實質性證據”的科學家們及主流媒體。

The head of WHO openly pushed back against the joint mission’s conclusion, and U.S. President Joe Biden ordered the intelligence community to reassess the lab-leak possibility. Eighteen scientists, including leaders in virology and evolutionary biology, signed a letter published in Science in May that called for a more balanced appraisal of the “laboratory incident” hypothesis.

世界衛組織領導人公開，將反對上述聯合任務的結論推回。不過，美國總統喬拜登命令情報部門，重新評估實驗室外洩的可能性。18位科學家，包括病毒學及演化生物學的領導者，在5月發表於《科學》期刊的一封信上署名，呼籲對“實驗室意外事件”之假設，進行較平衡的評估。

Yet behind the clamor, little had changed. No breakthrough studies have been published. The highly anticipated U.S. intelligence review, delivered to Biden on 24 August, reached no firm conclusions, but leaned toward the theory that the virus has a natural origin.

不過，在此喧囂背後，鮮少有改變。因為，沒有突破性的研究曾被發表。備受期待之美國情報部門的審查，沒有獲得明確的結論，於2021年8月24日遞交拜登。不過，傾向該種病毒具有自然起源的理論。

Fresh evidence that would resolve the question may not emerge anytime soon. China remains the best place to hunt for clues, but its relative openness to collaboration during the joint mission seems to have evaporated.

解決此問題的新證據可能不會很快出現。中國仍然是找尋線索的最佳所在地。不過，在聯合任務期間，其對合作的相對開放性，似乎已經消失。

Chinese officials have scoffed at calls from Biden and WHO Director-General Tedros Adhanom Ghebreyesus for an independent audit of key Wuhan labs, which some say should include an investigation of notebooks, computers, and freezers.

中國官員們對來自拜登及世界衛組織秘書長譚德塞，對有些人表示應該包括，一項有關筆記本、電腦及冰櫃調查之武漢市重要實驗室，進行獨立審查的呼籲嗤之以鼻。

Chinese vice health minister Zeng Yixin said such demands show “disrespect toward common sense and arrogance toward science.” In response to the increasing pressure, China has also blocked the “phase 2” studies outlined in the joint mission’s March report, which could reveal a natural jump between species.

中國副衛生部長，Zeng Yixin表示，這種要求顯示“對常識的不尊重及對科學的傲慢”。在對日益增多的壓力反應上，中國也已經阻擋諸多，於聯合任務可能揭露，物種間自然躍進之3月報告中，被概述的“第二階段”研究。

Despite the impasse, many scientists say the existing evidence—including early epidemiological patterns, SARS-CoV-2’s genomic makeup, and a recent paper about animal markets in Wuhan—makes it far more probable that the virus, like many emerging pathogens, made a natural “zoonotic” jump from animals to humans.

儘管此僵局，諸多科學家表示，包括初期流行病學模式、SARS-CoV-2的基因體組成及最近一篇，有關在武漢動物市場之論文的現有證據。使得該種病毒，如同諸多新興病原體般成為一種，從動物躍進到人類之自然“人畜共通疾病”的可能性更大得多。

Some of those clues have led Michael Worobey, an evolutionary biologist at the University of Arizona who has done groundbreaking work on the origins of HIV and the 1918 flu, further away from the lab-origin theory. Although he always viewed it as less likely, he co-signed the Science letter calling for a more thorough investigation of the lab-leak hypothesis.

其中有些線索已經引領了，美國亞利桑那大學，在人類免疫缺陷病毒(HIV：Human Immunodeficiency Virus)及1918年流感之起源，曾進行開拓性研究的演化生物學家，Michael Worobey進一步遠離實驗室起源的理論。雖然他一直認為，這較不可能。不過，他共同簽署了，於《科學》期刊，呼籲更徹底調查實驗室外洩假設的信函。

But like at least one other signatory, he now has second thoughts about that plea, in part because it heightened political tensions. “I think it probably did more harm than good in terms of actually having relevant information flow out of China,” he says.

不過，至少如同另一位簽署者，目前有關那請求，他有第二種想法。部分因為這提升了，政治緊張局勢。他宣稱：「他認為，從實際獲得由中國流出的有關聯信息方面來說，這可能導致更多弊大於利。」

Jesse Bloom, an evolutionary biologist at the Fred Hutchinson Cancer Research Center who spearheaded the Science letter, says the lab-origin theory will continue to thrive until the Chinese government becomes more cooperative.

上述《科學》期刊的信函領頭者，美國弗雷德哈欽森癌症研究中心的演化生物學家，Jesse Bloom表示，實驗室起源的理論將持續旺盛，直到中國政府變得更為合作。

“I don’t think Chinese scientists are less trustworthy,” says Bloom, who has sharply criticized China for attempting to “obscure” data about early COVID-19 cases. “But it’s clear that, at least in relation to this topic, they are operating under strong constraints imposed by the government.”

曾嚴厲批評中國，試圖“遮掩”有關早期COVID-19病例數據的Bloom宣稱：「他不認為，中國科學家們較不值得信賴。不過很顯然，至少關於此話題，他們是在政府施加的諸多強大壓力下，進行運作。」

AT ITS CORE, the lab-origin hypothesis rests on proximity. A novel coronavirus, genetically linked to bats, surfaced in a city that’s home to the Wuhan Institute of Virology (WIV), which has long specialized in studying bat coronaviruses, and two smaller labs that also handle those viruses. One or more lab workers could have become infected by accident, then passed the virus to others.

在其核心，實驗室起源的假設是基於相近。一種遺傳上與蝙蝠被聯繫起來的新型冠狀病毒，出現於長期一直專攻研究蝙蝠冠狀病毒的武漢病毒學研究所(WIV)，及兩所也處理那些病毒之較小實驗室的所在城市。一名或多名實驗室工作人員可能曾意外遭感染，之後將該種病毒傳給其他人。

Lab accidents are not unheard of, after all: SARS-CoV, the coronavirus that causes severe acute respiratory syndrome (SARS), has infected researchers as many as six times after the global outbreak of that disease ended in July 2003.

畢竟，實驗室的意外事件並非聞所未聞：導致嚴重急性呼吸系統徴候群(SARS)的冠狀病毒SARS-CoV，在2003年7月結束之那種疾病全球爆發後，曾感染多達六倍的研究人員。

A researcher’s infection with SARS-CoV-2 needn’t have happened in Wuhan itself. Alina Chan, a gene therapy researcher at the Broad Institute who also co-signed the Science letter, cites a study by WIV researchers, published in 2018, that sampled blood from 218 people who lived 1000 kilometers from the city near caves that were home to coronavirus-infected bats.

研究人員感染SARS-CoV-2未必曾發生於武漢市。也共同簽署《科學》期刊信函的博德研究所基因療法研究員，Alina Chan引用了武漢病毒研究所，研究人員們於2018年所發表，一項從居住於距離該城市1千公里，靠近遭冠狀病毒感染之蝙蝠棲息洞穴，218人取得血液樣本的研究。

Six of these people had antibodies that suggested prior infections by SARS-related bat coronaviruses, a branch of the family tree that includes SARS-CoV, SARS-CoV-2, and close cousins. Wuhan researchers have visited that area repeatedly and “easily could have picked up something from a human who already carried a human-adapted form of a SARS-related virus,” Chan says.

其中6人具有，暗示先前遭與SARS相關之蝙蝠冠狀病毒感染的抗體。此病毒是包括，SARS-CoV、SARS-CoV-2及近親病毒之家族樹的一個分支。Chan宣稱：「武漢病毒研究所的研究人員們，曾多次造訪那地區。因此，可能曾輕易從一位，已經攜帶適應人類之SARS相關類型病毒的人，獲得某種東西。」

Shi Zhengli, the lead bat coronavirus scientist at WIV, denies that anyone at the lab fell ill around the time SARS-CoV-2 emerged. In an email interview with Science in July 2020, she wrote that “all staff and students in the lab” were tested for SARS-CoV-2 and related coronaviruses and were negative.

武漢病毒研究所的首要蝙蝠冠狀病毒科學家，Shi Zhengli否認，於該實驗室裡的任何人，在大約SARS-CoV-2出現時，生病。在2020年7月一項接受《科學》期刊的電子郵件採訪時，她寫道，“於該實驗室的所有職員及學生”皆接受SARS-CoV-2及相關冠狀病毒的檢測，結果呈陰性。

Still, in January, days before Trump left office, the U.S. Department of State said the “government has reason to believe that several researchers inside the WIV became sick in autumn 2019.”

儘管如此，在2021年1月，川普離任前幾天，美國國務院表示“政府有理由相信，武漢病毒研究所內部若干名研究人員，在2019年秋季染病。”

And on 23 May, The Wall Street Journal reported the existence of an “undisclosed U.S. Intelligence report” that said three WIV researchers “sought hospital care” in November 2019. The story had no details about their illnesses, and some have noted that Chinese hospitals provide care for all ailments, including minor ones.

而在2021年5月23日，《華爾街日報》報導過存在一份，宣稱三名武漢病毒研究所研究人員，於2019年11月“尋求醫院護理”之“未公開的美國情報報告”。該報導沒有攸關他們的疾病詳情，不過有些人曾指出，中國醫院為所有疾病提供護理，包括小病。

Virologist Robert Garry of Tulane University finds it improbable that a Wuhan lab worker picked up SARS-CoV-2 from a bat and then brought it back to the city, sparking the pandemic. As the WIV study of people living near bat caves shows, transmission of related bat coronaviruses occurs routinely.

美國杜蘭大學的病毒學家，Robert Garry認為，武漢實驗室的工作人員，不大可能從蝙蝠感染上SARS-CoV-2，之後將其帶回該城市，從而觸發此大流行病。因為，武漢病毒研究所，有關生活於靠近蝙蝠洞穴之人的研究顯示，相關之蝙蝠冠狀病毒的傳染經常發生。

“Why would the virus first have infected a few dozen lab researchers?” he asks. The virus may also have moved from bats into other species before jumping to humans, as happened with SARS. But again, why would it have infected a lab worker first? “There are hundreds of millions of people who come in contact with wildlife.”

他質疑：「為何這種病毒會最先感染幾十名實驗室研究人員？」如同與SARS發生般，這種病毒在躍進到人類之前，也可能已經從蝙蝠轉移到其他物種。不過另一方面，有數億與野生動物有接觸的人，為何這種病毒會最先感染實驗室工作人員？

Another data point argues against infected researchers playing a role, Garry says. As the WHO joint mission report spells out, clusters of early COVID-19 cases had links to multiple Wuhan markets around the same time, which Garry says supports the idea of infected animals or animal traders bringing the virus to the city.

Garry表示，另一個數據點(數據點是一個離散的信息單元。一般而言，任何單一事實皆是數據點。)成了，遭感染之研究人員們，扮演一種角色的反證。如同世界衛組織聯合任務報告清楚說明般，初期的COVID-19病例群，大約在同一時間，已經與多個武漢市場有關聯性。Garry表示，這支持了遭感染的動物或動物貿易商，將該種病毒帶到此城市的見解。

A lab worker with COVID-19 would have had to make “a beeline not just to one market, but to several different markets,” he says. “You can’t rule it out, but then why the markets? Why not a soccer game or a concert or 100 other different scenarios?”

他宣稱：「一名罹患COVID-19的實驗室工作人員，可能曾必需不只是一直線的前往一個市場，而是前往若干不同市場。無法排除它，不過在那情況下，為何是此些市場？為何不是一場足球比賽、音樂會或其他1百種不同腳本？」

But David Relman, a Stanford University microbiome researcher who also co-signed the Science letter, questions the “hopelessly impoverished” data on the earliest COVID-19 cases. “I just don’t think we have enough right now to say anything with great confidence,” Relman says.

不過，也共同簽署上述《科學》期刊信函之美國史丹佛大學微生物體研究員，David Relman質疑，有關最初COVID-19病例之“一貧如洗的”數據。Relman宣稱：「他只是不認為，目前咱們有足夠的正當理由，以高度信心說任何事情。」

Linfa Wang, a molecular virologist at the Programme in Emerging Infectious Diseases at Duke-NUS Medical School in Singapore who has collaborated extensively with WIV on bat coronavirus studies, has a simpler reason for dismissing the lab-leak hypothesis.

新加坡杜克-新加坡國立大學所屬醫學院，新興傳染病計劃之分子病毒學家，針對蝙蝠冠狀病毒研究，曾與武漢病毒研究所廣泛合作的Linfa Wang，有個更簡單的理由，駁回實驗室外洩的假設。

“Accidents can only happen when you already have a live virus in culture that can leak,” Wang says. Bat coronaviruses are notoriously hard to grow. Shi told Science last year that her lab had more than 2000 bat fecal samples and anal and oral swabs that tested positive for coronaviruses.

Wang宣稱：「當在可能外洩之培養液中，已經有活病毒時，意外事件才會發生。」眾所周知，蝙蝠冠狀病毒很難生長。去年，Shi告訴《科學》期刊，她的實驗室有2千多個蝙蝠糞便樣本，及冠狀病毒檢測呈陽性的肛門與口腔拭子。

But the lab had only isolated and grown three viruses over 15 years, Shi said, and none closely resembled SARS-CoV-2. Some have questioned Shi’s veracity—she may well be under pressure from the Chinese government—and noted inconsistencies in her statements, but several scientific collaborators outside China have high regard for her integrity.

不過Shi表示，在15年間，其實驗室僅曾離析及培養三種病毒，且無一與SARS-CoV-2很相似。有些人曾質疑Shi的誠實性(她很可能是在來自中國政府的壓力下)，並指出其陳述中的諸多矛盾。不過，中國以外的若干科學合作者，已經高度重視她的正直。

Wang also discounts reports that WIV has live bats. “Many years back” the lab conducted immune studies on live bats, Wang says, but these were not of the genus Rhinolophus—the only one found to harbor SARS-related coronaviruses—which no lab has ever been able to keep alive in captivity.

Wang也不予全信，武漢病毒研究所有活蝙蝠的諸多報導。他表示，“多年前”該實驗室針對活蝙蝠，進行了諸多免疫的研究。不過，此些並不屬於 蹄鼻蝠屬(唯一被發現窩藏與SARS有關之冠狀病毒的蝙蝠)。沒有實驗室曾經能使這種蝙蝠，存活於豢養的環境中。

A great deal of speculation about the pandemic’s origin has centered on six men who developed severe respiratory illnesses in 2012 after clearing bat feces from a copper mine in Mojiang, in China’s Yunnan province. Three of them died.

有關此大流行病起源的大量猜測曾集中於，在2012年，清除中國雲南省墨江銅礦之蝙蝠糞便後，罹患了嚴重呼吸道疾病，其中三名死亡的6名男子身上。

Lab-origin proponents have suggested the men were infected with a coronavirus, a belief fed by a 2013 master’s thesis that provided no direct evidence. That bat virus, they argue, either was SARS-CoV-2 or was turned into it through genetic engineering.

實驗室起源的提議者們曾暗示，此些男子感染上一種冠狀病毒。這是由2013年一篇，沒有提供直接證據之碩士論文，加深的一種見解。他們認為，那種蝙蝠病毒不是SARS-CoV-2，就是透過基因工程轉變成的SARS-CoV-2。

When the miners fell ill, Shi and co-workers were asked to sample bats at the mine, which they did on several occasions. They discovered nine new SARS-related viruses. One of these, dubbed RaTG13, is 96.2% genetically identical to SARS-CoV-2, the closest overall similarity yet found.

當此些礦工生病時，Shi及同事們被要求，在礦坑中，採取蝙蝠樣本。她們曾多次進行過這種採樣。發現了，九種與SARS有關的新病毒。其中之一，被稱為RaTG13的病毒，基因上96.2%與SARS-CoV-2完全相同。這是迄今為止，所發現最接近整體的相似性。

A loose-knit group whose members call themselves DRASTIC—for the Decentralized Radical Autonomous Search Team Investigating COVID-19—has driven a heated discussion about possible links between RaTG13 and SARS-CoV-2.

有關RaTG13與SARS-CoV-2之間的可能關聯性，一支成員們自稱為DRASTIC(Decentralized Radical Autonomous Search Team Investigating COVID-19：分散式激進自主搜索團隊調查COVID-19)之編組鬆散的團隊，已經推動了熱烈的討論。

Shi has reported that her lab tested blood from the miners and did not find evidence of coronaviruses or antibodies to them. Wang, who helped with these analyses, finds the assertion that the team suppressed evidence of SARS-CoV-2’s link to the Mojiang mine preposterous.

Shi曾報告說，其實驗室測試了來自此些礦工的血液，沒有發現他們具有冠狀病毒或抗體的證據。協助進行此些分析的Wang，發現該團隊隱瞞了 SARS-CoV-2與墨江礦坑無意義之關聯性證據的武斷之說。

“We wanted to prove that a coronavirus caused the deaths,” says Wang, who grew up in Shanghai but is now an Australian citizen. “If we proved that another SARS-like virus was in humans in China that would have been scientifically brilliant,” he says. “It’s a Science or Nature paper. No scientist is going to wait for this to leak.”

在上海長大，不過目前是澳大利亞公民的Wang宣稱：「他們想證實，死亡是由冠狀病毒所引起。倘若他們證實，另一種類似SARS的病毒，存在於中國的人類中，那會是科學上輝煌的發現。這是一篇《科學》或《自然》的論文。沒有科學家會等待此洩露。」

Even Bloom agrees with that logic. “That’s one of the strongest arguments you can make against a lab accident,” he says. “On the other hand, I feel like a lot of these questions could be resolved pretty easily by enhanced transparency.”

甚至Bloom也同意那種邏輯。他宣稱：「那是人們能反對實驗室意外事件，提出的最有力論據之一。另一方面，他覺得好像，藉由提高透明度，很多此些問題能很輕易被解決。」

IN THE MOST ELABORATE lab-leak scenarios, SARS-CoV-2 is not a naturally occurring virus, but was created at WIV. That would bring worldwide condemnation on China, but it would also devastate the field of virology.

在最精心製作之實驗室外洩漏的腳本中，SARS-CoV-2不是自然產生的病毒，而是在武漢病毒學研究所被創造的。那會招致全世界對中國的譴責，此外這也會破壞病毒學領域。

There has been an intense debate over the past decade about the scientific value of “gain-of-function” (GOF) studies, which deliberately create pathogens that are more virulent or more transmissible to humans—or both—than their natural cousins. Some say GOF studies can help identify and thwart future threats, but critics argue the potential benefits don’t outweigh the risk of creating and unleashing pandemic pathogens.

有關故意創造出病原體，比其天然同類物更毒或更易傳染給人類(或兼具兩者)之諸多“功能獲得”(GOF)研究的科學價值，在過去十年中，一直有激烈的爭論。有些人表示，GOF研究能有助於確認及阻擾未來的威脅。不過，批評者認為潛在的益處，不會勝過產生及釋放出大流行病之病原體的風險。

Shi has created chimeric viruses in the past to get around the difficulty of growing coronaviruses isolated from bats. In work with Peter Daszak of the EcoHealth Alliance and Wang, described in a 2017 paper in PLOS Pathogens, WIV made chimeras using the genetic “backbone” of one of the bat coronaviruses her lab could culture and genes that coded for the surface protein, called spike, from newly found coronaviruses.

於過去，Shi曾創造嵌合體病毒以克服，培養從蝙蝠離析之冠狀病毒的困難。在2017年，發表於《PLOS Pathogens》期刊的一篇論文中描述了，在與美國生態健康聯盟Peter Daszak及Wang的研究中，武漢病毒學研究所使用Shi實驗室，能培養的蝙蝠冠狀病毒之一的遺傳“骨幹”，及為被稱為棘突之表面蛋白質編碼的基因，製造了嵌合體。

Scientists disagree about whether this was GOF research. Shi says it was not, because the hybrid viruses her group created were not expected to be more dangerous than the original strains.

對於是否這是GOF研究，科學家們意見不合。Shi表示這不是，因為其團隊創造的混合病毒，預期不會比原來的病毒株更為危險。

Anthony Fauci, head of the U.S. National Institute of Allergy and Infectious Diseases, which helped fund the study, told Congress it does not qualify as GOF research under NIAID’s guidelines. Relman finds the GOF label “vague and confusing” and instead describes this as “unnecessarily risky research.”

協助資助該項研究的美國國家過敏暨傳染病研究所(NIAID)，所長Anthony Fauci告訴國會，根據NIAID的指導方針，這並不具備GOF研究的條件。 Relman發現GOF的標語“籠統且混亂”，是將此描述為“不必要的冒險研究”。

Definitions aside, if Shi was creating chimeric viruses, SARS-CoV-2 may have been one of them, lab-leak proponents say. They also note biosecurity measures at the lab were relaxed. In her 2020 Science interview, Shi denied conducting chimeric virus experiments beyond those reported in the 2017 paper, but she acknowledged doing some coronavirus studies in biosafety level 2 facilities.

實驗室外洩的支持者表示，撇開定義不談。倘若Shi是創造嵌合體病毒，則SARS-CoV-2可能曾是其中之一。他們也指出，於該實驗室的生物安全措施是鬆弛的。Shi在2020年《科學》期刊的採訪中，否認進行了超出那些於2017年論文中，報導的嵌合體病毒實驗。不過，她承認在生物安全2 級設施中，進行了一些冠狀病毒研究。

That’s one level lower than even Ralph Baric, a coronavirus researcher at the University of North Carolina, Chapel Hill, who has collaborated with Shi, thinks is appropriate. Shi stressed that the work complied with all Chinese regulations.

那甚至比，美國北卡羅萊納大學教堂山分校，曾與Shi合作過的冠狀病毒研究員，Ralph Baric認為是合適的還低一級。Shi強調，這項研究符合中國的所有法規。

Still, many scientists contend that SARS-CoV-2 can’t be a lab concoction because no known virus is close enough to have served as its starting material. Some have countered that RaTG13, the virus found in the Mojiang mine, could have been that backbone.

然而，諸多科學家堅決認為，SARS-CoV-2不可能是種實驗室的調製物。因為，沒有已知的病毒類似的足以作為其起始材料。一些人反駁說，在墨江礦坑中發現的RaTG13病毒，可能曾是那種骨幹。

That makes no sense, asserts a “critical review” by Garry, Worobey, and 19 other scientists that Cell published online on 19 August. More than 1100 nucleotides, the building blocks of RNA, separate the genomes of the two viruses, and the differences are scattered in a way that doesn’t suggest deliberate engineering.

力陳由Garry、Worobey及其他19位科學家，2021年8月19日發表於網路版《細胞》期刊的一項“批判性審查”，那是無意義的。因為，超過1100個核苷酸(RNA的構材)，區分兩種病毒的基因體，且此些差異是以一種，不會使人聯想到蓄意工程改造的方式分散。

“Nobody has the sort of insight into viral pathogenesis to design something as really devious as SARS-CoV-2,” Garry says. Three other bat viruses more similar to SARS-CoV-2 than RaTG13 in some key genomic regions are also unlikely to have been used as a template for the pandemic virus, according to the paper.

Garry宣稱：「無人具有病毒發病機制的這類洞察力，來設計如SARS-CoV-2真正狡猾的東西。」根據此論文，在某些關鍵基因體區域，比RaTG13更類似SARS-CoV-2的其他三種蝙蝠病毒，也不可能曾被使用作為，此大流行病的病毒模板。

The “smoking gun” evidence that SARS-CoV-2 was engineered, in the words of virologist and Nobel laureate David Baltimore, has not held up either. Spike has a cleavage site, a spot where a human enzyme named furin cuts the protein, which helps SARS-CoV-2 infect cells.

以病毒學家暨諾貝爾獎得主David Baltimore所說的話，SARS-CoV-2是被工程改造的“確鑿證據”，也不曾被提出。棘突具有一處，被稱為弗林蛋白酶的人類酵素，切割協助SARS-CoV-2感染細胞之蛋白質的劈裂位點。

Since early in the pandemic, lab-origin proponents have claimed that no SARS-related bat coronaviruses have this feature, leading to speculation that a lab added the site to a virus so it could infect humans. When retired New York Times writer Nicholas Wade made the case for a lab leak this spring, the furin cleavage site, buttressed by Baltimore’s provocative words, was an essential part of the argument.

打從此大流行病初期以來，實驗室起源的支持者曾聲稱，無與SARS相關的蝙蝠冠狀病毒具有這種特徵。致使實驗室將該位點添加到一種病毒中，因此它能感染人類。今年(2021年)春天，當退休的《紐約時報》作家，Nicholas Wade提出有利於實驗室外洩的理由時，遭Baltimore挑釁性言論支持的弗林蛋白酶劈裂位點，是爭論的核心部分。

But it’s dead wrong, say many coronavirus specialists and evolutionary biologists. The SARS-related coronaviruses are in the beta genus, one of four in the Coronaviridae family. Several members of that genus feature furin cleavage sites, which appear to have evolved repeatedly.

不過，諸多冠狀病毒專家及演化生物學家表示，這完全錯誤。SARS相關的冠狀病毒屬於β屬，是冠狀病毒家族中的四種之一。那屬的若干成員，以顯然已經重複演化之弗林蛋白酶劈裂位點為特徵。

And one SARS-CoV-2–related virus, described in a Current Biology paper last year by a team led by Shi Weifeng of Shandong First Medical University, has three of the four amino acids that constitute the furin cleavage site, which is “strongly suggestive of a natural zoonotic origin” for SARS-CoV-2, the authors concluded.

在去年(2020年)，一支由中國山東第一醫學大學，Shi Weifeng領導之團隊，發表於《當代生物學》期刊的一篇論文中，描述了一種與SARS-CoV-2相關的病毒，具有構成弗林蛋白酶劈裂位點之四種氨基酸中的三種。此些撰文者們下了結論，對SARS-CoV-2而言，這“強烈使人聯想到一種天然的人畜共患病起源”。

Baltimore has backpedaled the statement. He did not know several bat beta coronaviruses have the furin cleavage site, he acknowledged in an email to Science. “[T]here is more to this story than I am aware of,” he wrote. “The furin cleavage is the most ridiculous stuff,” Wang says.

Baltimore已經背棄此聲明。他在給《科學》期刊的一封電子郵件中，承認不知道有若干種蝙蝠β冠狀病毒，具有弗林蛋白酶劈裂位點。他寫道：「此情節有比他意識到的還多。」 Wang宣稱：「弗林蛋白酶劈裂是最不合理的內容。」

Instead of genetically manipulating a virus, a lab could also have created SARS-CoV-2 by passaging, a technique in which researchers grow a virus in a lab dish or an animal, harvest it, and repeat the process again and again, allowing mutations to accrue.

取代遺傳上操縱病毒，藉由繼代移種(研究人員們在實驗室培養皿或動物中，培養、獲得病毒，且一再重複此過程，從而容許發生突變的一種技術)，實驗室也可能曾經創造出SARS-CoV-2。

But again, they would have needed to start with a close relative of SARS-CoV-2. There’s no evidence that this precursor existed in any lab. And passaging in cell cultures often deletes the furin cleavage site or makes viruses weaker.

不過同樣，他們會需要以SARS-CoV-2的近親開始。沒有這種前身物，存在於任何實驗室中的證據。細胞培養液中的繼代移種，通常刪除弗林蛋白酶劈裂位點，或使病毒變較弱。

Even the U.S. intelligence community during the Trump administration discounted the suggestion that SARS-CoV-2 was “manmade.” The report requested by Biden, which sought input from several groups in the intelligence community, similarly concludes that the virus “was probably not genetically engineered.” (It also said there was “broad agreement” that it “was not developed as a biological weapon.”)

甚至川普政府期間的美國情報部門也不全信，SARS-CoV-2是“人造”的暗示。由拜登要求的報告，徵求了來自情報部門中若干團隊的信息，同樣得出該種病毒“可能不是經基因改造”的結論。(此報告也表示，有這“不是被開發作為生物武器”之“廣泛一致的看法”。)

THE JOINT MISSION REPORT from WHO, which runs more than 300 pages and delves into everything from the viral sequences of the earliest cases to pharmacy sales, has several little-noticed findings that make a natural origin appear more likely than a lab leak, says Kristian Andersen, an evolutionary biologist at Scripps Research who co-authored the recent Cell paper with Garry and Worobey.

美國斯克里普斯研究所，與Garry及Worobey合撰，該最近發表於《細胞》期刊之論文的演化生物學家，Kristian Andersen表示，來自世界衛生組織聯合任務，長達300多頁深入研究，從最早病例的病毒序列，到藥房銷售之所有事物的報告，有若干使得自然起源比實驗室外洩，更有可能之鮮少引人注目的發現。

“It wasn’t the perfect report,” he says, but it was “a great start to a collaborative study on understanding the origin of SARS-CoV-2.”

他宣稱：「這不是完美的報告。不過，這是針對瞭解SARS-CoV-2起源之合作研究的一種極佳開端。」

The earliest official announcement about the pandemic came on 31 December 2019, when Wuhan’s Municipal Health Commission reported a cluster of unexplained pneumonia cases linked to the city’s Huanan seafood market.

有關此大流行病的最早官方公告，出現於2019年12月31日。當時武漢市衛生委員會報告了，與該市華南海鮮市場有關之一系列，原因不明的肺炎病例。

The WHO report devotes much attention to details about Huanan and other Wuhan markets, but also cautions that their role remains “unclear” because several early cases had no link to any market. But after reading the report, Andersen became more convinced that the Huanan market played a critical role.

世界衛組織的報告，非常專注於華南及其他武漢市場的詳情。不過，也發出此些市場角色“不明朗”的警告。因為，若干早期病例與任何市場沒有關聯。不過，讀完此報告後，Andersen變得更加相信，華南市場扮演了一種關鍵角色。

One specific finding bolsters that case, Wang says. The report describes how scientists took many samples from floors, walls, and other surfaces at Wuhan markets and were able to culture two viruses isolated from Huanan. That shows the market was bursting with virus, Wang says: “In my career, I have never been able to isolate a coronavirus from an environmental sample.”

Wang表示，一個具體的發現支持了這種情況。該報告描述了，科學家們如何從武漢市場的地板、牆壁及其他表面採集許多樣本，且能夠培養出從華南市場離析出的兩種病毒。那顯示，此市場(華南)充斥著病毒。Wang宣稱：「在他的職業生涯中，未曾能從環境樣本中，離析出冠狀病毒。」

The report also contained a major error: It claimed there were “no verified reports of live mammals being sold around 2019” at Huanan and other markets linked to early cases. A surprising study published in June by Zhou Zhao-Min of China West Normal University and colleagues challenged that view.

該報告也具有一項重大錯誤：它聲稱在華南及其他與早期病例有關的市場，“沒有活體哺乳動物，在2019年期間，被出售之未經證實的報告”。 一項由中國華西師範大學Zhou Zhao-Min及同事們，於2021年6月發表之令人驚訝的研究，挑戰了那種考察。

It found nearly 50,000 animals from 38 species, most alive, for sale at 17 shops at Huanan and three other Wuhan markets between May 2017 and November 2019. (The researchers had surveyed the markets as part of a study of a tick-borne disease afflicting animals.)

該研究發現，於2017年5月至2019年11月期間，在華南及其他三處武漢市場的17家店舖銷售了，來自38個物種，近5萬隻大部分是活的動物。(此些研究人員曾經調查這些市場，作為研究一種折磨動物之蜱傳疾病的一部分。)

Live animals can more easily transmit a respiratory virus than meat from a butchered one, and the animals included masked palm civets, the main species that transmitted SARS-CoV to humans, and raccoon dogs, which also naturally harbored that virus and have been infected with SARS-CoV-2 in lab experiments.

活體動物比來自經屠宰動物的肉，更容易傳播呼吸器官的病毒。而這些動物包括，將SARS-CoV傳播給人類之主要物種的蒙面棕櫚果子狸，及也自然窩藏那種病毒且在實驗室中，曾被感染上SARS-CoV-2的貉。

Minks—a species farmed for fur that has acquired SARS-CoV-2 infections from humans in many countries— were also abundant. “None of the 17 shops posted an origin certificate or quarantine certificate, so all wildlife trade was fundamentally illegal,” Zhou and his colleagues wrote in their paper.

貂(一種在諸多國家已經從人類，獲得SARS-CoV-2感染之為了毛皮，被養殖的物種)也很豐富。在Zhou及其同僚們的論文中，他們論述：「上述17家店舖無一張貼，原產地證明或檢疫證明。因此，所有野生動物交易根本是非法。」

It’s unclear why the international members of the WHO joint mission were not told about the live market mammals by their Chinese counterparts. “I’m really disappointed that came out after [the report],” says WHO’s Maria Van Kerkhove, who acknowledges contributing to the oversight herself because she mistakenly ignored a draft of the paper that the authors sent her when they first submitted it in October 2020.

目前不清楚，為何世界衛組織聯合任務的國際成員，沒被中國對應的人告知，有關活體市場的哺乳動物。世界衛組織的Maria Van Kerkhove宣稱：「在此報告之後傳開，她真的很失望。」她承認，由於錯誤忽視，當此些撰文者，於2020年10月首次提交時，送給她的該論文草稿，導致了她本人的這種疏漏。

Worobey says the paper played a key role in tilting his thinking away from the lab-origin hypothesis. “The fact that early [COVID-19] cases were linked to the market, and that the market was selling what were very likely intermediate hosts?” he says. “All of that is probably trying to tell us something.”

Worobey表示，在使其見解偏離實驗室起源假說上，此論文扮演了一種關鍵角色。他宣稱：「是因為，初期COVID-19病例與市場有關，及市場所出售的很可能是中間宿主？的事實。」

Worobey suspects that after a SARS-CoV-2 progenitor jumped from animals to humans, it pingponged back and forth, steadily adapting to its new host. This could have happened at the market and gone unnoticed for weeks, as the outbreak only surfaced when several people became severely ill, a relatively rare outcome of a SARS-CoV-2 infection.

Worobey懷疑，在SARS-CoV-2前身從動物躍進到人類後，傳來傳去，平穩地適應新宿主。這可能曾發生於市場上，且進展沒有被發覺達數星期，因為當若干人病得很重時，疫情爆發才浮現。這是SARS-CoV-2感染，一種相對罕見的結果。

Or the virus could have first infected animal farmers in remote villages. “If this happened in a small town, it’s quite probable it would never have taken off,” says William Hanage, an evolutionary biologist at Harvard University. Then animal traders might have brought the virus to markets in Wuhan, a city of 11 million.

或該種病毒可能曾首先感染了，於偏遠村莊的動物農場主人。之後，動物交易商可能曾將此種病毒帶到，擁有1100 萬人口之武漢市的諸多市場。美國哈佛大學演化生物學家，William Hanage宣稱：「倘若發生於一個小鎮上，這很可能絕不會爆發。」

Linda Saif, a veterinarian at Ohio State University, Wooster, says China’s enormous fur industry is at the top of her list of places to hunt for SARS-CoV-2’s precursors. Saif cites a report showing the vast majority of the world’s pelts from raccoon dogs and foxes—both canids, a family readily infected with SARS-CoV-2—are from animals farmed or trapped in China (see graphic, above). The country produces half of the world’s mink pelts, too.

美國俄亥俄州立大學伍斯特分校的獸醫，Linda Saif表示，中國龐大的毛皮產業，是其尋找SARS-CoV-2前身的首選之地。Saif引用了一份，顯示絕大多數世界毛皮來自貉及狐狸(這兩種犬科動物，這是一科容易感染 SARS-CoV-2的動物)，是源自在中國被飼養或被陷捕之動物的報告。中國也生產半數世界的貂皮。

An epidemic of African swine fever virus in pigs might also, indirectly, have helped spark the pandemic, a perspective in the 27 August issue of Science suggests. China’s mass culling of pigs because of that virus led to record high pork prices in November 2019. Food consumers and producers may have resorted to alternative types of meat, leading to "increased wildlife-human contacts."

2021年8月27日版《科學》期刊的一個觀點暗示，非洲豬瘟病毒於豬中的流行，也可能曾間接助長觸發此大流行病。由於那種病毒，中國大規模撲殺豬隻，導致了2019年11月，豬肉價格創下歷史新高。食品消費者及生產者可能已經採用替代型的肉類，而導致“增加了野生動物與人類的接觸。”。

SO WHERE TO NOW? Bloom would like more details about the earliest human cases of COVID-19 and says WIV should share bat coronavirus sequences in a database it removed from the internet in September 2019, claiming the site had been hacked. “That could put a lot of this to rest,” he says.

那麼現在去哪裡？Bloom想要更多有關最早COVID-19人類病例的詳情，且表示武漢病毒學研究所應該，在其2019年9月，從聲稱已遭駭客入侵之互聯網站刪除的數據庫中，分享蝙蝠冠狀病毒序列。他宣稱：「這可能平息很多問題。」

Sales data from Wuhan markets could help, too. If researchers could trace who farmed or trapped the live animals sold there and who delivered them to the markets, those people could be interviewed and perhaps sampled for evidence of past infections.

來自武漢市諸市場的銷售數據，也可能有所助益。倘若研究人員們能追踪誰飼養或陷捕，在那裡銷售的活體動物，及誰將牠們運送到此些市場。就能採訪那些人，且或許能取得過去感染證據的樣本。

In a comment published by Nature on 25 August, the international members of the joint mission warned it’s time to get on with “phase 2” because the window for some studies is closing. But WHO is reconfiguring the team.

在2021年8月25日，發表於《自然》期刊的一則評論中，聯合任務的國際成員們提醒，這是進行“第二階段”的時候。因為，一些研究的窗口關閉中。不過，世界衛組織正進行重新配置該團隊。

It recently announced a new International Scientific Advisory Group for Origins of Novel Pathogens (SAGO) that will provide “rapid advice” to launch the follow-up studies described in the mission report, but also study the origins of future outbreaks.

世界衛組織最近宣佈一支，將提供“快速建議”，以啟動任務報告中，所描述的後續研究，除此之外，也研究未來爆發之起源的新型病原體起源的科學諮詢團隊(SAGO)。

The Chinese government has shown no signs it will welcome SAGO members, but Wang is hopeful it will have a change of heart: “In an ideal world, we need a Chinese collaboration.”

中國政府沒有展現會歡迎SAGO成員的跡象。不過，Wang希望中國政府會改變心意：在理想的世界中，咱們需要中國的合作”。

Chinese scientists are conducting their own studies into potential natural origins, but few outside the country know details. “Unfortunately, finding out what is being done is getting harder by the day because the lab-leak stuff has turned COVID origins into a major political weapon,” says one Western researcher who asked not to be identified. “My colleagues in China are nervous and feeling great pressure.”

中國科學家們正對潛在的自然起源，進行他們自己的研究。不過，國外很少人知曉細節。一位不願透露姓名的西方研究人員宣稱：「不幸的是，發現正在進行的事情，變得日益艱難。因為，實驗室外洩的題材已經將COVID起源，變成一種主要的政治武器。他在中國的同事們很緊張，且感到莫大壓力。」

China has been pushing the theory that the virus came from another country—maybe brought in on frozen food, or, according to baseless propaganda, concocted at a U.S. military lab. “It’s comical,” Worobey says. “The big picture here is China is doing everything it can to push the narrative that this pandemic started outside of China.”

中國一直在推動，這種病毒來自另一個國家的理論。可能是在冷凍食品上被帶進入，或根據毫無基礎的宣傳，是在美國軍事實驗室被調製的。 Worobey宣稱：「這很可笑。此時大情勢是，中國正竭盡全力推動，這種流行病始於中國境外的論述。」

He suspects that while rejecting the lab-leak theory, the Chinese government is also unenthusiastic about pursuing a natural origin, fearing that proof would expose China to further blame for a pandemic even if the discovery exonerated Chinese scientists.

他懷疑，儘管拒絕實驗室外洩的理論，有關追尋自然起源，中國政府也不熱衷，擔心即使此發現解除了科學家的罪責，證據會使中國曝露於大流行病的更多非難。

But even without China’s cooperation, there are ways to move ahead. Some studies elsewhere have already yielded intriguing leads. Researchers have found coronaviruses in bats in neighboring countries that suggest evolutionary pathways from an ancestor of SARS-CoV-2 to the pandemic virus.

不過，即使沒有中國的合作，也有諸多前進的方法。其他地方的一些研究已經產生了，諸多引人好奇的線索。在若干鄰近國家的蝙蝠中，研究人員們已經發現，暗示從SARS-CoV-2原種，到此大流行病毒之演化途徑的冠狀病毒。

More clues may come from studies in Southeast Asia of wild pangolins—the only other species to date found to harbor a close SARS-CoV-2 relative. Researchers can also hunt for cases outside of China that predate the December 2019 outbreak.

更多的線索可能來自，東南亞有關野生穿山甲的研究。這是迄今為止，被發現窩藏一種，接近SARS-CoV-2相對病毒的唯一其他物種。在中國以外，研究人員們也能尋找，於2019年12月爆發之前的病例。

One possibility, Wang says, is to check the blood of Wuhan visitors or residents who were in the city in the months before, including the 9000 athletes from more than 100 countries who attended the Military World Games there in October 2019. (A new antibody assay from his lab, he says, can distinguish between SARS-CoV-2 and related viruses that may have preceded it.)

Wang表示，一種可能性是檢測，2019年12月幾個月前，在武漢市的遊客或居住者，包括來自百餘國家，參與2019年10月世界軍人運動會之9千名運動員的血液。(他表示，來自其實驗室的一種新抗體分析，能在SARS-CoV-2與可能在它之前的相關病毒間作出區分。)

The search will never lead us to patient zero, the first person to be infected by SARS-CoV-2, Hanage says. “Humans are looking for a story,” he says. “They want Columbo to come in and just somehow get somebody to confess or show what actually happened.”

Hanage表示，此搜索絕不會引領咱們找到，第一個感染SARS-CoV-2的零號病人。他宣稱：「人們正在尋找一種由來。希望可倫坡(美國犯罪電視劇中，洛杉磯警察局的兇殺案偵探)上場，且只是以某種方式，讓某人承認或展現，到底發生了什麼。」

Instead, there are “possible stories” about SARS-CoV-2’s origin—some more probable than others—and stories that can be excluded, Hanage says. “And the space of possible stories in which there was a natural origin in or around the markets is much larger than the space of possible origins in which the Wuhan Institute of Virology is involved.”

不過Hanage表示，有關SARS-CoV-2的起源，有諸多“可能的由來”(有些比其他更可能)及若干能被排除的由來。“而在市場內或市場周圍有自然起源之可能由來的空間，比武漢病毒學研究所涉及之可能起源的空間更大得多”。

網址：https://www.science.org/content/article/why-many-scientists-say-unlikely-sars-cov-2-originated-lab-leak

翻譯: 許東榮