There has been a lot of debate on the origin of the SARS-CoV-2, the virus that caused the Coronavirus COVID-19 pandemic (2019 to ~ 2022).
Many people believe, without evidence, that it was a biological weapon (some say it was developed by the USA, others believe it was developed by China), others believe it was leaked from a research lab in China (the Wuhan Institute of Virology, or the Wuhan Center For Disease Control).
However, the evidence so far, while not final, points to a natural zoonotic origin of the virus. In simple words, the virus was present in animals, and from there, jumped to humans.
Was It A Biological Weapon
The hypothesis that the virus was a biological weapon is laughable at best.
Several arguments go against this hypothesis:
First, any biological weapon is intended to destroy or disable the demographic that dominates fighting soldiers. That means young people 18 to 40 years old. Specifically, the weapon needs to take out the manpower of active duty, either by killing them, or disabling them for an extended period of time. If that happens, the side that released the virus can achieve the objectives of the war (occupy/annex territory, force the defeated side to concede, ...etc.).
What we have seen instead is a virus that kills mostly elderly people (not of fighting age), and a case fatality rate (CFR) of only 2-3% of those infected dying from the disease.
Second, any country that releases a biological weapon must have strong defenses against it, so it does not affect its own soldiers and populace. This is usually well tested vaccines.
What we have seen is that no country had immunity against this virus, nor were vaccines available anywhere in the first year. There was no country that was 'ready' for this pandemic, whether in Personal Protection Equipment (masks), hospital emergency departments, medical staff, beds, ...etc.
So this hypothesis is mere speculation, with the events proving that it does not stand on any facts.
The Most Plausible Scenario
This is the most likely scenario, so far:
The most parsimonious explanation, that accounts for all the scientifically rigorous evidence listed below, is that the jump was from bats to a wild or farmed animal (most likely raccoon dogs) in southern China. Those infected animals were trucked to Wuhan's wet market. Either in the farm, or along the route, or in the Wuhan market, two humans got infected, one with lineage A and another with lineage B. One of these lineages died out, and the other continued to spread around the world, mutating, as viruses do, and is still going on, albeit with much lower virulence since the Omicron variant in early 2022 ...
The body of evidence so far supports a natural emergence of the virus that caused the pandemic.
On the contrary, there are no data to support the alternate hypotheses (biological weapon or lab leak, intentional or accidental).
Recent Beta Coronavirus Pandemics Were Zoonotic
If one thinks a bit about recent events, we had three outbreaks from the beta coronaviruses sub family in less than two decades!
Two of them were pandemics, with varying scales:
- SARS in 2003, from civet cats
- MERS in 2012, from camels
- SARS-COV-2 in 2019, from raccoon dogs (or other species)
And there are 4 other coronaviruses that infect humans with common cold like symptoms (about 16% of annual cases of common cold).
What Virologists Say
No one has to take anything that I say as truth.
Listen to experts in the field instead, and published peer reviewed research.
First, there is this video, with 3 virologists, all with Ph.D.s in the field.
Two of them are retired virology professors at respected universities.
One of them wrote the textbook, literally, on virology (Vincent Racaniello)
TWIV 1155: Listen from 00:02:20 to 01:10:00
They discuss two papers, one briefly (they term that a "snippet"), and the other in more depth.
The other paper is discussed in more depth (starting at ~ 00:30:00) is one of many that support the natural zoonotic origin, with two separate spillover events from animal to humans in the Huanan wet market in Wuhan.
The paper is: Genetic tracing of market wildlife and viruses at the epicenter of the COVID-19 pandemic.
Also, a genetic analysis of animals in the Wuhan wet market is zeroing in on a short list of animals that possibly helped spread it to people.
Other Viruses Do This All The Time
And it is not only beta coronaviruses that continues to mutate and infect different species.
Influenza has been doing this for longer than beta coronaviruses, as far back to 1918 (at least).
The 2024 strain of H5N1 influenza jumps to mammals regularly.
For example, seals in Patagonia, and dozens of tigers died in Vietnam.
Also in 2024, dairy cows in the USA have been infected, and there are human cases too, though it is not clear how they contracted the virus (water foul, or some mammal such as pet dogs who ate dead infected birds, ...).
China's Role In The Uncertainty
The pandemic's definitive origin is still undetermined because the Chinese government acted fast, and those actions resulted in an information blackout.
They took swabs from the market, disinfected everything, then destroyed the animals at the Wuhan market.
Their actions could have been driven by:
a) public health concerns, so as to limit the spread, or
b) avoiding blame for yet another pandemic because of exotic species being consumed (SARS, then SARS CoV 2), or
c) an active cover-up, or
d) something else entirely.
Which one is it? That is up for debate.
The genetic sequences from the market swabs are the only hard evidence that we have on the early days of the pandemic.They were published initially by Chinese researchers on science database for nucleic acid sequences. The Chinese authorities shut that down, then they were republished later.
There is also no information on whether the Chinese traced the animals to the farms that raised them, or the wild areas they were captured in. If they did that tracing, they are not sharing the results.
The issue is that Chinese authorities, unlike most Western style democracies, immediately suppresses any information on a any disaster.
Here is an example from from an unrelated incident: When horror hits China, the first instinct is shut it down.
So whatever the intentions were, the actions causes this information void that we have.
What About US Intelligence Agencies?
But some say: intelligence agencies have said the lab leak theory cannot be ruled out.
And that is not a strong argument ...
First, there is no consensus among these intelligence agencies. According to the report of the Directorate of National Intelligence, four intelligence agencies have assessed that natural exposure caused the pandemic, with low confidence. Up until January 2025, only two agencies preferred the lab origin, with different conclusions: the FBI thought the Wuhan Institute of Virology is to place of exposure, and the Department of Energy thought that the Wuhan Center for Disease Control is the focal point.
Second, these assessments usually depend on the mindset, and political leaning of their leadership. This is even clearer when the second Trump administration started, the new Trump appointed CIA head changed the agency's stance to favor the lab leak theory! That alone makes these intelligence reports a less than conclusive opinion.
Moreover, as the above article says: "The [new] finding is not the result of any new intelligence"!
Finally, and perhaps most importantly: those are intelligence agencies, so by definition they don't publish the data backing up their conclusion. We have to take their word for it without any scrutiny.
By contrast, we have the experts overwhelmingly for the natural origin.
I'll that that over the intelligence agencies any day ...
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