clock menu more-arrow no yes
Medical workers examine samples from local residents to be tested for Covid-19 at a mobile test lab in Yangzhou, China.
Meng Delong/VCG via Getty Images

The lab leak hypothesis — true or not — should teach us a lesson

As Covid-19 continues to wreak havoc, humans still aren’t doing enough to prevent the next pandemic.

The origins of the novel coronavirus that caused the Covid-19 pandemic remain a mystery. US intelligence agencies have now completed a 90-day probe into the origins of SARS-CoV-2, but their classified findings, according to the New York Times, were inconclusive as to whether the virus escaped from a laboratory in Wuhan, China, or made a natural jump from an animal into a human.

Yet to prevent the next pandemic, scientists don’t need a definitive answer about the genesis of Covid-19. Regardless of how the coronavirus outbreak started, researchers say the world urgently needs to do more to prevent both lab leaks and so-called “spillover” infections from animals. Tracing the route of the virus is an important scientific question, but countries can and should take steps to reduce these risks now, even without a final answer.

“We don’t have to wait for all these results to start acting,” said Andrew Weber, senior fellow at the Council on Strategic Risks and a former assistant secretary of defense for nuclear, chemical, and biological defense programs under President Barack Obama. “There’s some big policy decisions that we can make now.”

Right now, the Covid-19 pandemic is continuing to rage around the world; dozens of countries are fighting the spread of the highly contagious delta variant, and many are struggling to get enough vaccines to protect themselves. Figuring out just where the virus came from would do little to mitigate the current crisis.

It may be years before the world gets a satisfying answer, and one may never emerge. But in the meantime, from regulating wildlife markets to transparency around biological research, there are many measures that can reduce the risk of future outbreaks.

Both spillovers and laboratory leaks of pathogens have happened before

There were warnings that humanity was at risk of a pandemic even before Covid-19, and at several points the world has come scarily close.

Several dangerous pathogens have escaped laboratories in the past and gone on to infect people. In 1977, an outbreak of H1N1 influenza erupted on the border between China and the Soviet Union. Based on a genetic analysis of the strain, many researchers concluded the virus escaped from a lab. Smallpox, meanwhile, was eradicated from the wild in 1977; the following year, Janet Parker, a photographer at Birmingham Medical School in the UK, became infected and later died. The building she worked in housed a research laboratory where scientists were studying smallpox.

In 2004, at least two unnamed researchers contracted the SARS virus at the Chinese National Institute of Virology in Beijing. One of the researchers went on to infect her mother, who later died, as well as a nurse at the hospital where her mother was treated. The outbreak led to 1,000 people being quarantined or placed under medical supervision. At the time, the World Health Organization (WHO) reported there may have been similar outbreaks of SARS in Taiwan and Singapore that also may have originated in labs.

The “Falcon” air-inflated testing labs for Covid-19 nucleic acid testing in China’s Jiangsu Province on July 27.
Li Bo/Xinhua via Getty Images

There have been even more alarming close calls where scientists were exposed to dangerous pathogens due to equipment failure or lax adherence to containment protocols.

However, every known lab leak to date has involved a pathogen that was previously identified. There has never been a confirmed case of a never-before-seen virus escaping a research facility.

At the other end of the spectrum of possibilities, virologists point out that the vast majority of pathogens that infect humans originate in nature, and almost all come from interactions with animals. Over the past century, about two new viruses per year have been discovered in humans, most of which spilled over from animals, according to a 2012 paper in Philosophical Transactions of the Royal Society B.

“All these spillovers, wherever they are, it’s because human activity is encroaching upon animal activity,” Vincent Racaniello, a virologist at Columbia University, told Vox in June.

Influenza, for example, is found in birds, poultry, pigs, and seals. HIV likely originated in chimpanzees. Measles has an ancestor in cattle.

In fact, another coronavirus, the 2003 SARS virus, was found to have jumped from bats to civet cats before making the leap to humans. And scientists have warned for years that another bat coronavirus could trigger an outbreak in people.

The debate over Covid-19’s origins may never be resolved to everyone’s satisfaction

Many researchers in the early days of the Covid-19 pandemic were quick to attribute the emergence of the SARS-CoV-2 virus to a natural occurrence, likely a human contact with a bat coronavirus via an intermediary. Two recent papers, one in the journal Science and one in the journal Cell, emphasized this conclusion, citing genetic evidence tracing both the lineage of the virus and the circumstances in China in late 2019 that increased the likelihood of humans coming into contact with wild animals that could harbor the pathogen.

Still, some scientists have argued for closer scrutiny of the possibility that the novel coronavirus escaped from a lab. The most basic hypothesis is that a worker at the Wuhan Institute of Virology was infected by a naturally occurring virus under study there. There is no direct evidence for this, nor any indication that SARS-CoV-2 or a progenitor was being studied at the lab, let alone that someone who worked there was infected. Wuhan is about 1,000 miles away from where the bats that harbor a similar virus are found, raising the question of how SARS-CoV-2 crossed that distance. The laboratory was also known to handle its viral samples at a lower safety level than most scientists recommend for such a pathogen. In addition, no one has found an animal that clearly hosted the virus or a precursor just before it leaped into humans.

More fringe ideas are also circulating, like the notion that the virus was deliberately engineered to be more dangerous or deliberately released as a bioweapon. There’s no evidence for these claims.

With the passage of time, however, it’s becoming more difficult for scientists to study the origins of Covid-19. In a recent article in the journal Nature, WHO researchers warned that time is running out: “The window of opportunity for conducting this crucial inquiry is closing fast: any delay will render some of the studies biologically impossible.”

Another complication is that the question of where the virus came from has become a political issue domestically and internationally. Within the US, some politicians have been eager to blame a lab for the pandemic and shift the blame to China.

That, in turn, has become a major source of friction between the United States and China. Chinese officials stopped cooperating with a WHO investigation into the origins of the coronavirus earlier this year and responded with their own allegations that the virus originated in a US lab (for which there is no evidence).

And without cooperation from Chinese authorities, it’s unlikely that a definitive answer — one way or the other — will emerge anytime soon.

Scientists already know how to stop lab leaks

There are many ways to improve safety in laboratories and install safeguards to prevent dangerous diseases from escaping and wreaking havoc. Even scientists who think the emergence of SARS-CoV-2 was a natural event say that preventing lab leaks should be a high priority.

Gigi Gronvall, senior scholar at the Johns Hopkins Center for Health Security, said it’s important to think about two key concepts: “Biosafety” is about protecting people who work with pathogens from the things they are studying, usually through accidents. “Biosecurity” is preventing misuse of pathogens via deliberate actions.

Both are essential to prevent leaks of biological agents, but they’re often afterthoughts when it comes to conducting research on pathogens. “It’s hard to make this exciting,” Gronvall said. “That is why very often the money goes to research, and biosafety is less emphasized.”

One way to enhance biosafety is to deploy several different methods of containment in a laboratory. For instance, biosafety level 3 precautions for handling pathogens that can spread through the air include only handling samples in “biological safety cabinets” that filter air, controlling lab access with two sets of self-locking doors, and wearing respirators, eye protection, and lab coats. It also includes routine medical screening of lab workers.

“Ideally, if there is any kind of accident, there are still multiple layers before it becomes an issue for anyone outside a laboratory,” Gronvall said.

Journalists and security personnel gather near the entrance of the Wuhan Institute of Virology after a visit by a team from the World Health Organization on February 3.
Ng Han Guan/AP

Biosafety also hinges on the type of studies being conducted. Of particular concern is gain-of-function research, in which pathogens are deliberately modified to become more dangerous to humans. The goal is to map out potential changes that could emerge in the wild and develop ways to counter them before they become major threats. It’s a controversial form of research, and some have alleged that the Wuhan Institute of Virology was conducting such experiments — though, again, there is no evidence this occurred. US officials have also been adamant that they have not funded any gain-of-function research, either in the US or abroad.

Some scientists say this kind of research should not be conducted at all because the risk of an escape is too great, but others say gain-of-function studies can be conducted safely with appropriate precautions.

“Lab incidents will still occur. A robust biosafety and biosecurity system, along with appropriate institutional response, helps to ensure that these incidents are inconsequential,” biosafety experts David Gillum (Arizona State University) and Rebecca Moritz (Colorado State University) wrote for the Conversation. “The challenge is to make sure that any research conducted — gain-of-function or otherwise — doesn’t pose unreasonable risks to researchers, the public and the environment.”

Building a robust biosecurity system requires cooperation from institutions ranging from laboratories to regulators to governments. It demands rigorous oversight to enforce safety standards. Transparency among institutions about the kinds of biological research they’re conducting, as well as potential mishaps and accidents, is also critical. But there’s a pervasive fear among laboratories and the individuals who work there that disclosing problems will hurt their reputations.

“If there is a biosafety incident, it is very hard to get that addressed in a way that doesn’t cause problems for an institution,” Gronvall said. “They have a lot of incentives to keep it under wraps.”

That’s also why it’s been hard to know whether China is stonewalling investigators because of a potential lapse in laboratory protocol or out of general distrust of other countries and institutions like the WHO. “A bat could’ve walked out of a cave wearing a name tag and China would behave the same way,” Gronvall said.

Fixing this requires a change in the culture surrounding biological research to create an environment where mistakes and problems are discussed openly and addressed immediately. Inspections, monitoring, and documentation would also make it harder to sweep any problems under the rug.

What’s tougher is enforcing these principles around the world. There is an international agreement restricting research on biological weapons, the Biological Weapons Convention, but there’s no similar agreement for general biological research. Many countries have their own research programs for pathogens, and it’s the Wild West when it comes to what standards are used and what studies are done.

“There’s really no international body that has the authority to oversee biological security or biological safety,” said Weber, from the Council on Strategic Risks. “We should work with [the] international community to adopt real standards for biosecurity and for high-risk research.”

Some pathogen laboratories, like the US Army’s Fort Detrick in Maryland, already have exchange programs with researchers around the world. More exchanges and international inspections of biological research labs could help ensure that every facility adopts best practices and upholds the highest safety and security standards. But setting up such a regime requires trust and cooperation, and that’s in short supply.

“Natural” spillovers, which often have human causes, can be prevented, too

Pathogens found in the wild have infected people for millennia, but there are ways to tame this force of nature. “What we can do is reduce the rate of exposure of humans,” said Andrew Dobson, professor of ecology and evolutionary biology at Princeton University.

For example, a key route for new human diseases is contact with wildlife. Such interactions increase as cities sprawl into the wilderness and people venture further into remote areas in search of food, fuel, and raw materials. When humans destroy habitats, especially through deforestation, they force animals to flee to new areas and interact with people in cities and suburbs. In one paper published in the journal Science in 2020, Dobson reported that when more than 25 percent of original forest cover is lost, it’s much more likely for humans and their livestock to come into contact with wildlife that may carry diseases.

“That’s what’s exposing people to the hosts and the carriers of these viruses,” said Dobson. Drastically reducing deforestation and placing strict limits on how much people can encroach into forests, grasslands, and deserts can slow the emergence of dangerous new parasites, viruses, bacteria, and fungi.

Domesticated animals, particularly livestock, can also be a source of new diseases. The combination of changes in land use and factory farming of cattle, chicken, and hogs can increase the risk of a pathogen hopping between species.

Another way to reduce the chances of a spillover is to close unregulated markets that sell wildlife as food, ingredients for medicines, or materials for clothing. Phasing out legal wildlife markets and screening the health of animals that humans do come into contact with would also reduce the risks of new diseases jumping into people. “There needs to be [many] more international treaties around that to protect people,” said Dobson.

Live animals, including local wildlife, on sale in a bird market in Bali, Indonesia. Live animal markets have come under international scrutiny since the Covid-19 outbreak.
Amilia Roso/The Sydney Morning Herald via Getty Images

The hurdle is that the wildlife trade is quite lucrative. The legal wildlife market is worth about $300 billion, while estimates of the value of illegal wildlife trading can be as high as $23 billion. So reducing some of the highest-risk forms of wildlife trade also demands an economic solution for people whose livelihoods would be affected, such as helping them find new jobs.

Surveillance — actively looking for dangerous pathogens in the wild to stay ahead of outbreaks — is another important tactic, but there are some risks. Sending researchers into remote areas to collect samples and study them could expose them to dangerous diseases.

“We need to think more about the precautions people take and the security level in those labs,” Dobson said. “[But] the amount we’ll learn will significantly reduce the risk of future outbreaks.”

The history of narrowly averted pandemics is full of crucial lessons

Beyond probing the roots of the Covid-19 pandemic, it’s also worth investigating close calls of the past. Viruses like the original SARS virus in 2003, for example, had the potential to go global but didn’t. The virus itself had some traits that prevented it from spreading further, and while many of the countries most acutely affected by the outbreak, like China and Vietnam, learned critical public health lessons, much of the rest of the world remained complacent.

In a 2013 paper in the Journal of Management, researchers looking at problems with uncrewed NASA missions highlighted the important lessons that can be found in near-miss scenarios like this. “Disasters are rarely generated by large causes,” the authors noted. “Instead disasters are produced by combinations of small failures and errors across the entire organizational system.” So whether SARS-CoV-2 came from a lab or a natural event, a lot of other things also had to go wrong for it to become an international crisis.

When all these factors don’t align in a particular instance and fail to produce a disaster, it’s easy to take the wrong lesson — that humans were adequately prepared or that the status quo of science and public health is good enough already. But it’s dangerous to ignore close calls, whether it’s a near collision between satellites or a new pathogen that was narrowly contained.

“If near-misses masquerade as successes, then organizations and their members will only learn to continue taking the risks that produced the near-miss outcome until a tragedy occurs,” the researchers wrote.

That’s why it’s important to study the factors behind not just the Covid-19 pandemic but also other outbreaks like those of Ebola, SARS, and MERS, which raised alarms and revealed weaknesses in national and global public health systems.

We may not unravel the origins of SARS-CoV-2 anytime soon — if ever. But by treating both spillovers and lab leaks as urgent risks right now, scientists, health officials, and governments can protect us all from outbreaks of the future.


A simple solution to endless school quarantines


How Walgreens’ sloppy Covid-19 test registration system exposed patient data


Why Biden’s approval numbers have sagged, explained by an expert

View all stories in Explainers