By Tsang Kwong-Hoi and Wan Sui-Lun
Whether the SARS-CoV-2 virus originated itself from nature or was reconstituted from laboratory is a subject that is being keenly explored by the scientific community since the pandemic's outbreak. Proponents of the former often cited two documents to support their arguments:
Document A: A Statement (Calisher et al, 2020) issued by a group of 27 scientists and published in Lancet in mid-February 2020. Extract of their claims and conclusion are in the box below:
We stand together to strongly condemn conspiracy theories suggesting that COVID-19 does not have a natural origin. Scientists from multiple countries have published and analysed genomes of the causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and theyoverwhelmingly conclude that this coronavirus originated in wildlife, as have so many other emerging pathogens.
Document B: A Letter to editor published in Nature Medicine written by Kristian Andersen and four other bio-scientists (Andersen et al., 2020) in March 2020. The letter rejects all probable artificial modification done to the virus SAR-CoV-2 on two grounds (see box below):
Ground 1: 'Computational analyses predict that the interaction' of the virus SARS-CoV-2 with human cells is 'not ideal'. Moreover, in actual interaction, the virus can still bind to human cells with 'optimal' and 'high-affinity binding'. Hence, this virus is 'most likely the result of natural selection' and not 'emerged through laboratory manipulation'.
Ground 2: 'If genetic manipulation had been performed, one of the several reverse-genetic systems available for betacoronaviruses would probably have been used. However, the genetic data irrefutably show that SARSCoV- 2 is not derived from any previously used virus backbone.'
Our cross-examination of the supporting evidence presented in the two documents, however, discovered that the authors have committed a major logical fallacy of inventing assumptions to fit into their pre-determined conclusion. For that reason, we cannot concur with their argument that SAR-CoV-2 to be originated "purely" from nature is the only possible answer to the emergence of the present virus.
More importantly, we strongly disagree with their labelling of other scientists' ideas as conspiracy theory if these ideas do not recognize that SARS-CoV-2 has a natural origin. For this kind of labelling is against science. Quite the contrary, we advocate that incessant efforts should be undertaken to search for the "origin" and the "formation pathway" of this virus which has led it to its present form. Sorting out these two matters will help prevent this kind of tragic pandemic from re-occurrence.
Such labelling of others as conspiracy theorists blocks our search for the truth and over-simplifies the situation.
Critique on Document A
The 27 scientists argue conclusively that the present virus is originated from nature under the Law of Natural Selection, and that no artificial modification has been added to it before it started to infect humans. In supporting this claim, they cited 9 research papers (under the Statement's footnotes 2-10). But on careful examination of these 9 papers, we found that there is only one paper explicitly states that there is no synthetic part added to form the present virus. Its arguments are recapitulated in the second box above, and we will discuss them in the subsequent section.
Though all of the remaining eight papers do mention that the SARS-CoV-2 has bat as its ancestor, but none rejects the possibility and probability that artificial modification has been made to the parents of this virus. Such modification may include but not limited to the insertion of engineered parts or recombination of genetic sections from two or more viruses.
Additionally, all the eight papers focus mainly on matters such as elaborating the genome characteristics of the new virus, comparing it with existing known SARS-like viruses, discussing clinical features, pathogenicity, and infectivity caused by the new virus, and confirming that it uses the same cell entry receptor—(ACE2)—as SARS-CoV to infect human. The findings and discussions of these papers are unrelating to the claims of the 27 scientists.
Critique on Document B
In Document B, Andersen et al. have used two grounds to reject the probability of human modification done on the present virus (recapitulated in the second box above). But their claim was challenged by the French Nobel Laureate in Medicine and a world renowned virologist, Luc Montagnier recently. In a radio interview by the largest French Radio, RFI, Montagnier testified that the present virus is a man-made one (see the box below).
(Source: Extract of Interview of Luc Montagnier, RFI, April 19, 2020. Translated by the authors of this article)
Reporter: We understand that you must be surprised to find HIV genetic section in the present virus genome sequence. But can it be the consequence of natural genetic mutation. For example, may it be the consequence of an HIV patient contracted the present novel virus?
Montagnier: No, human bodies cannot influence viral genome in this way. To insert a gene encoded protein in the laboratory is relatively difficult a few years ago. But today, it is much easier.
Reporter: To you, the claim that the present virus is originated purely from nature is not plausible, and it must be the consequence of human manipulation?
Montagnier: Yes. This virus is reconstituted based on a coronavirus from bat. Then, it may be accidentally leaked from a lab. The so-called origination from a seafood market is just a legend.
Reporter: What is the purpose of producing this man-made virus for? Is it for producing bio-chemical weapon or for studying and producing HIV vaccines?
Montagnier: I reckon that the most rational explanation is for producing vaccine. Using a non-infective coronavirus as a vehicle to carry an HIV genome section for cultivating anti-HIV vaccines.
Reporter: What you have explained is very clear and horrible. You are a world known scholar and a Nobel Laureate. Nevertheless, will you be criticized as a conspiracist?
Montagnier: It is those who cover up the true picture should be called conspiracists. I have a lot of Chinese friends. I was in China in the last few weeks before the outbreak. I reckon that it would have been a lot easier if the Chinese Government told the world the true picture right on the onset. The true picture will be revealed to the world anyhow, especially when the present virus has the genetic section of HIV and other possible viral genome sequences. I do not mean to hold any one responsible. But it is a fact that people are doing various kinds of genetic experiments in China.
Montagnier: The Chinese Government needs to take responsibility for such covering up. Particularly, it should not prohibit the publishing of research papers relating to the origin of the virus. Such prohibition will project a wrong perception to people that today's science is not meant for revealing truth but for fitting to the will of a few. Doing this is a disastrous blow to science, because no one will continue to believe in science. Hence, I hope the Chinese Government may take up their due responsibility. They have already admitted that there are problems in the laboratories, but it needs to stride further.
According to Montagnier, the present virus can be made by inserting some very small synthetic parts into an existing SARS-like coronavirus. (This coronavirus may be one which has never been registered in public gene bank). The terrible side is that this insertion resembles a key genetic section of HIV. Though it is a very short section composed of only 12 nucleotides, less than 0.04% of the full genome sequence of 29,903 nucleotides for the present virus, but it carries some key viral functions of HIV. These functions allow the HIV to effectively fuse with and enter into human cell, hide itself for some time, and afterward progressively attack the immune system of the human hosts. According to Montagnier, technology advancement has made such synthetic work much easier and more accurate than a few years ago.
From the interview, readers can see that the Nobel Laureate holds a complete opposite stance on the origin of SARS-CoV-2 to that of Andersen et al. But who is right?
If we look at the two grounds proposed by Andersen et al., we can find grave logical faults in Andersen et al.'s arguments. For the first ground, they have assumed that if the virus is really a human construct, it must be designed by computers to generate its optimal features. But they have neglected the fact that researchers who want to test the pathogenicity and infectivity of a virus may not necessarily opt to design one with optimal features.
As researchers, Andersen et al. should know that cost and time effectiveness are always the more important considerations than the absolute perfectness of the bio-tools. For such types of research, most researchers will create a viral chimera (bio-product artificially made by recombination of genetic parts/backbones) with fit-for-purpose features rather than perfect features. Like Shi ZL, the Director of Wuhan institute of Virology, and Ralph Baric from US in 2015, they did not choose an optimal virus generated by computers, but copied and modified from existing viruses to fit into their purposes.
For the second ground, Andersen et al. argue that 'the genetic data irrefutably show that SARS-CoV-2 is not derived from any previously used virus backbone.' Again, they have assumed that the researchers who create a chimera must use genome sequence registered in public genome banks. But how about if the researchers have kept some undisclosed novel genome sequences at their stock and use them to do the type of research as described by Montagnier, and accidentally leak one of them out to cause this outbreak.
From the above exposition, readers can see that Andersen et al. have fallen into a typical fallacy of designing assumptions to fit into their pre-determined conclusions and take their assumptions as irrefutable facts.
WHO Takes Scientists' Opinions as Scientific Truth
Readers have to note that the two documents are letters/correspondence to the editors whose academic rigor cannot be compared to the standard of journal papers which record the authors' purpose, methods and empirical findings, discussion, and research limitations. But these two documents have not provided systematic information as such. Hence, the claims made in these two documents are only opinions of the authors and should not be taken as scientific truth. For scientific truth, it should be both objectively and subjectively certain. Quite the opposite, for opinions, they are objectively not certain and hence should not be taken as scientific truth.
It is important to point out that many news media take the opinions of these two documents as scientific truth. Worse still, the World Health Organization (WHO) also takes these opinions as truth and misleads the world by saying that 'all available evidence suggests that SARS-CoV-2 has a natural animal origin and is NOT a constructed virus'.  As an influential organization whose convictions affect the well-being of everyone in the world, they should demonstrate their prudence by listing the journal papers with which they support their claim that the present virus is not a constructed one. Opinion can only be taken as opinion by its very nature. It cannot become truth merely because it is an opinion of a group of scientists.
Conclusion：Mission Impossible, In Case Vital Information Hidden
With the exposition we have presented, readers can see that scientists who hold that SARS-CoV-2 is a virus purely from nature without any human manipulation cannot be conclusive. Likewise, the claim that this virus is an engineered chimera from lab is equally inconclusive. The cause of this impasse and indeterminateness to the origin of SARS-CoV is mainly due to the missing of some vital information.
Such information can only be obtained from the city, animals, and persons relating to the first few sites of the outbreak. Without the relevant government agencies to help chase up the animal dealers for their sourcing channels, collect the animal samples from the animal habitats, testing every member of the lab personnel, and lifting investigative restrictions on the key sites, scientists can only play around with computer analytic tools for hints.
At present, the tools that scientists used are overwhelmingly the "Phylogenetic Trees". But these analytical tools cannot accurately determine if there is any artificial recombination work added to the virus (See Martin el al., 2015, p.2) . If they can, scientists such as Andersen et al. would have used them to refute the claim that this virus is a human construct.
Empirical scientists are there to make conclusion and findings based on facts, and not there to offer pure reasoning and guessing. Pure reasoning and spinning are the job for politicians. If scientists are blocked by politicians from access to the above key elements and are asked to come up with a valid and reliable conclusion, it is simply a mission of impossibility. Politicians putting this mission impossible to scientists as a tactic to avoid responsibilities of finding the true origin of the virus is another form of conspiracy that everyone has to denounce.
Authors of this article
Bachelor Degree in Engineering, the University of Hong Kong; Master Degrees in Law and in Public Policy, the Australia National University; Master Degree in Education (Ed. Psy.), the Chinese University of Hong Kong.
Bachelor's degree in social sciences of the University of Hong Kong, Master's degree of Sophia University, Japan, previously stationed in Tokyo for an inter-government organization, Director of Greater China for an international accounting firm, member of the former Commission on Strategic Development of Hong Kong SAR Government.
 Calisher et al. Statement in support of the scientists, public health professionals, and medical professionals of China combatting COVID-19. Lancet Correspondence. 2020.
 Andersen, K.G., Rambaut, A., Lipkin, W.I. et al. The proximal origin of SARS-CoV-2. Nat Med 26, 450–452 (2020).
 RFI, Radio France Internationale, is a French public radio service that broadcasts in Paris and all over the world. EXCLUSIF - Pour le Pr Montagnier, SARS-CoV-2 serait un virus manipulé par les Chinois avec de l'ADN de VIH ! (podcast)
 Menachery et al. A SARS-like cluster of circulating bat coronaviruses shows potential for human emergence Nature Medicine, 21:12, 2015.
 This is part of the answer to the question: Is the source of the coronavirus causing COVID-19 known? Asked In the Section: Question & Answer, WHO.
 Martin, D. P., Murrell, B., Golden, M., Khoosal, A., & Muhire, B.. RDP4: Detection and analysis of recombination patterns in virus genomes. Virus Evolution, 1(1), vev003. 2015.