Editor's note: Zhu Huachen is an associate professor at the State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong. This is the first piece of the author's series on the origins of COVID-19. The article reflects the author's opinions and not necessarily the views of CGTN.

I was shocked at the moment when I learned that the intelligence community, rather than the top virologists, was asked by the U.S. government to provide a report on the source and origin of the SARS-CoV-2.

I felt offended.

Since when did agencies become experts on virus emergence? Isn't that an obvious insult to the scientific community? Especially to those who are working in this research field?

As a young scholar with a major research focus on the emerging infectious diseases, I am privileged to have been working together with some leading scientists, witnessing how they revealed the source and origin of many notorious pathogens step by step and how they provided professional advice to avert the epidemics time and time again successfully.

I know how their hard work and endeavor have led to our new understanding about the various viruses; and how their unremitting efforts have enlightened our world, making it a safer, healthier, and more comfortable place to stay.

However, with the COVID-19 becoming a devastating pandemic, rationality was replaced by toxic prejudice and groundless suspicion. Scientists working at the front line are forced to face endless criticisms and accusations. Laboratories that are supposed to serve as the combat zone against the virus became an ideological battleground. 

Sadly, we see the virus took away millions of lives; stigmatization of the virus origin became the verbal trick skillfully manipulated by the politicians. The world was torn apart, and the pandemic rages unscrupulously.

It's time for the scientific community to join together and take back the lead in scientific issues.

Where did the virus come from? How did we end up with this situation? What can we do to avert the pandemic?

Lessons learnt about coronavirus following the SARS outbreak

The identification of SARS coronavirus in 2003 came as a surprise to the virologists and has then brought a wave of research enthusiasm. Before that, only two human coronaviruses, i.e. 229E and OC43, were known to infect humans, causing common cold with mild to moderate symptoms.

At that time, the coronavirus world was largely a virgin land to most of the investigators. Our understanding of the prevalence and distribution of coronaviruses in nature was (and remains) actually very, very limited. But "undetected" does not necessarily mean that the viruses do not exist.

In 2004 and 2005, about four decades after the discovery of the first coronavirus, NL63 and HKU1 were isolated and found to have been circulating in the human populations for some time.

In 2012, the deadliest coronavirus to humans, MERS coronavirus, emerged and later proved to have been prevalent in dromedary camels for decades. Serological and virological evidence also supported that this virus was not only circulating in the Middle East but also in Africa, where 80 percent of the world's total dromedary population is supplied.

In 2021, a retrospective study reported a novel canine coronavirus derived from patients hospitalized with pneumonia during 2017-2018 in East Malaysia. One of them turned out to be a canine-feline recombinant alphacoronavirus.

Meanwhile, porcine delta coronavirus (PDCoV) was isolated from plasma samples collected in 2014-2015 from three Haitian children with acute undifferentiated febrile illness. This study is available on a pre-print online journal only a few months ago.

In total, there are at least nine coronaviruses that have been documented to affect humans. Besides, coronavirus is now recognized as a virus family with high genetic diversity, broad host range and global distributions. Notably, it can infect birds, fish, and almost any kind of mammalian species, leading to a wide spectrum of diseases with zoonotic potential.

It was the outbreak of the epidemic that stimulated scientific discovery and exploration. Yet, our understanding of the virus is actually seriously lagging behind the occurrence of the epidemic. However, with the advance of science and technology in the coronavirus research field, it can be predicted that many unknown gaps in the virus evolutionary branches will be filled in.

Our knowledge of coronavirus obviously surged in the past 18 years, but there are still a lot more of unknown areas worth exploring. When scientists are working to fill up this vacuum, the COVID-19 hit the world, and conspiracy theories took place where science is absent.

Lab leak? When scientists are presumed to be guilty 

Since the day when scientists start to collect biological samples and manipulate potentially infectious agents, concerns about biosafety arise, and the possibility of lab leaking occurs.

Human beings have a need for a sense of control over the external environment, and we are seeking for consistency in our understanding of the world. We fear uncertainty and the unknown. Therefore, wherever there is a mysterious disaster, conspiracy theories contribute the easiest explanation to it, making us feel that our understandings are still in accordance with our previous experience or belief.

In the case of COVID-19, when conclusive evidence is yet to be identified for its exact source, the most convenient option is to blame the local institutes of virology and the researchers. The more they did before or during the outbreak, the higher chance their workers were exposed to the virus, and the higher possibility that they might make a mistake.

Every piece of information that leads us closer to the natural origin now became an accusation against the scientists. Whoever did the better job and found more viruses will be the more targeted suspect. Any labs that possess any infectious sample may potentially be the next victim. How ironic!

Where is our sense of rationality? Where is the presumption of innocence as the legal principle in our modern civil law systems? Without any high level of evidence, how can we prove that the scientists are guilty?

When researchers are accused of working on the SARS-related virus, or providing useful tools for coronavirus research, who do you think would bother to work out the truth and solutions in the future?

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