This article is about the hypothesis proposing SARS-CoV-2 came from a laboratory. For bioweapon conspiracy theories, see COVID-19 misinformation § Bio-weapon.
The COVID-19 lab leak theory, or lab leak hypothesis, is the idea that SARS-CoV-2, the virus that caused the COVID-19 pandemic, came from a laboratory. This claim is highly controversial; most scientists believe the virus spilled into human populations through natural zoonosis (transfer directly from an infected non-human animal), similar to the SARS-CoV-1 and MERS-CoV outbreaks, and consistent with other pandemics in human history.[1] Available evidence suggests that the SARS-CoV-2 virus was originally harbored by bats, and spread to humans from infected wild animals, functioning as an intermediate host, at the Huanan Seafood Market in Wuhan, Hubei, China, in December 2019.[5][6] Several candidate animal species have been identified as potential intermediate hosts.[13] There is no evidence SARS-CoV-2 existed in any laboratory prior to the pandemic,[14][15][16] or that any suspicious biosecurity incidents happened in any laboratory.[17]
Many scenarios proposed for a lab leak are characteristic of conspiracy theories.[18] Central to many is the misplaced suspicion about the proximity of the outbreak to a virology institute that studies coronaviruses, the Wuhan Institute of Virology (WIV). Most large Chinese cities have laboratories that study coronaviruses,[19] and virus outbreaks typically begin in rural areas, but are first noticed in large cities.[20] If a coronavirus outbreak occurs in China, there is a high likelihood it will occur near a large city, and therefore near a laboratory studying coronaviruses.[20][21] The idea of a leak at the WIV also gained support due to secrecy during the Chinese government's response.[14][22] The lab leak theory and its weaponization by politicians have both leveraged and increased anti-Chinese racism.[23] Scientists from WIV had previously collected virus samples from bats in the wild, and allegations that they also performed undisclosed work on such viruses are central to some versions of the idea.[24] Some versions, particularly those alleging genome engineering, are based on misinformation or misrepresentations of scientific evidence.[25][26][27]
The idea that the virus was released from a laboratory (accidentally or deliberately) appeared early in the pandemic.[28][29] It gained popularity in the United States through promotion by conservative personalities in early 2020,[30] fomenting tensions between the U.S. and China.[31] Scientists and media outlets widely dismissed it as a conspiracy theory.[32][33] The accidental leak idea had a resurgence in 2021.[34] In March, the World Health Organization (WHO) published a report which deemed the possibility "extremely unlikely", though the WHO's director-general said the report's conclusions were not definitive.[35] Subsequent plans for laboratory audits were rejected by China.[22][36]
Most scientists remain skeptical of the possibility of a laboratory origin, citing a lack of any supporting evidence for a lab leak and the abundant evidence supporting zoonosis.[15][37] Though some scientists agree a lab leak should be examined as part of ongoing investigations,[38][39]politicization remains a concern.[40][41] In July 2022, two papers published in Science described novel epidemiological and genetic evidence that suggested the pandemic likely began at the Huanan Seafood Wholesale Market and did not come from a laboratory.[16][42][5]
^See numerous reliable sources which support this:
Holmes EC, Goldstein SA, Rasmussen AL, Robertson DL, Crits-Christoph A, et al. (September 2021). "The origins of SARS-CoV-2: A critical review". Cell (Review). 184 (19): 4848–4856. doi:10.1016/j.cell.2021.08.017. PMC8373617. PMID34480864. As for the vast majority of human viruses, the most parsimonious explanation for the origin of SARS-CoV-2 is a zoonotic event...There is currently no evidence that SARS-CoV-2 has a laboratory origin. There is no evidence that any early cases had any connection to the WIV, in contrast to the clear epidemiological links to animal markets in Wuhan, nor evidence that the WIV possessed or worked on a progenitor of SARS-CoV-2 prior to the pandemic.
Bolsen T, Palm R, Kingsland JT (October 2020). "Framing the Origins of COVID-19". Science Communication. 42 (5): 562–585. doi:10.1177/1075547020953603. ISSN1075-5470. PMC7484600. PMID38603006. S2CID221614695. Individuals may learn about the origins of COVID-19 through exposure to stories that communicate either what most scientists believe (i.e., zoonotic transmission) or through exposure to conspiratorial claims (e.g., the virus was created in a research laboratory in China).
Robertson L (2 March 2023). "Still No Determination on COVID-19 Origin". FactCheck.org. Retrieved 24 May 2023. most scientists suspect a zoonotic spillover in which the virus transferred from bats, or through an intermediate animal, to humans — the same way the SARS and MERS coronaviruses originated.
Gajilan AC (19 September 2021). "Covid-19 origins: Why the search for the source is vital". CNN. Retrieved 24 May 2023. The zoonotic hypothesis hinges on the idea that the virus spilled over from animals to humans, either directly through a bat, or through some other intermediary animal. Most scientists say that this is the likely origin, given that 75% of all emerging diseases have jumped from animals into humans.
McDonald J (28 June 2021). "Where Did COVID-19 Start? The Facts and Mysteries of Its Origin". NBC 5 Dallas-Fort Worth. Retrieved 24 May 2023. The default answer for most scientists has been that the virus, SARS-CoV-2, probably made the jump to humans from bats, if it was a direct spillover — or, more likely, through one or more intermediate mammals.
MCKEEVER A (6 April 2021). "We still don't know the origins of the coronavirus. Here are 4 scenarios". National Geographic. Retrieved 24 May 2023. The most controversial hypothesis for the origin of SARS-CoV-2 is also the one that most scientists agree is the least likely: that the virus somehow leaked out of a laboratory in Wuhan where researchers study bat coronaviruses.
Ball P. "Three years on, Covid lab-leak theories aren't going away. This is why". www.prospectmagazine.co.uk. The leading theory now backed by most scientists is that the virus arose in wild bats and found its way into animals (perhaps via a pangolin or a civet cat) sold at the Huanan Seafood Wholesale Market in Wuhan.
Jackson C (21 September 2020). "Controversy Aside, Why the Source of COVID-19 Matters". GEN - Genetic Engineering and Biotechnology News. Retrieved 24 May 2023. Most scientists studying the origins of COVID-19 have concluded that the SARS-CoV-2 virus probably evolved naturally and infected humans via incidental contact with a wild or domesticated animal.
McCarthy S (16 September 2021). "Bat-human virus spillovers may be very common, study finds". South China Morning Post. Retrieved 24 May 2023. Questions have been raised about whether the virus could have leaked from a laboratory studying related viruses in Wuhan – a scenario most scientists...feel is less likely than a natural spillover.
Danner C (26 May 2021). "Biden Joins the COVID Lab-Leak-Theory Debate". Intelligencer. Retrieved 24 May 2023. There continues to be no evidence at all for the conspiracy theory that SARS-CoV-2, the virus that causes COVID-19, was developed as some kind of bioweapon, and most scientists believe that the majority of available evidence indicates the virus jumped from animal to human.
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^ abHolmes EC (14 August 2022). "The COVID lab leak theory is dead. Here's how we know the virus came from a Wuhan market". The Conversation. Archived from the original on 4 September 2022. Retrieved 4 September 2022. For the lab leak theory to be true, SARS-CoV-2 must have been present in the Wuhan Institute of Virology before the pandemic started. This would convince me. But the inconvenient truth is there's not a single piece of data suggesting this. There's no evidence for a genome sequence or isolate of a precursor virus at the Wuhan Institute of Virology. Not from gene sequence databases, scientific publications, annual reports, student theses, social media, or emails. Even the intelligence community has found nothing. Nothing. And there was no reason to keep any work on a SARS-CoV-2 ancestor secret before the pandemic.
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^Jacobsen R (29 June 2021). "Inside the risky bat-virus engineering that links America to Wuhan". MIT Technology Review. Archived from the original on 20 July 2021. Retrieved 20 July 2021. Ebright believes one factor at play was the cost and inconvenience of working in high-containment conditions. The Chinese lab's decision to work at BSL-2, he says, would have 'effectively increas[ed] rates of progress, all else being equal, by a factor of 10 to 20'.
^Moritsugu K (22 July 2021). "China rebuffs WHO's terms for further COVID-19 origins study". Associated Press. Archived from the original on 5 September 2021. Retrieved 6 September 2021. Zeng ... added that speculation that staff and graduate students at the lab had been infected and might have started the spread of the virus in the city was untrue.
^Cite error: The named reference Consensus was invoked but never defined (see the help page).
^Jacobsen R (13 May 2021). "Top researchers are calling for a real investigation into the origin of covid-19". MIT Technology Review. Archived from the original on 4 August 2021. Retrieved 4 August 2021. The lab leak hypothesis has already become highly political. In the US, it has been embraced most loudly by Republican lawmakers and conservative media figures... The resulting polarization has had a chilling effect on scientists, some of whom have been reluctant to express their own concerns, says Relman.