The emergence and spread of infectious diseases with pandemic potential occurred regularly throughout history. Major pandemics and epidemics such as plague, cholera, flu, severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) have already afflicted humanity. The world is now facing the new coronavirus disease 2019 (COVID-19) pandemic. Many infectious diseases leading to pandemics are caused by zoonotic pathogens that were transmitted to humans due to increased contacts with animals through breeding, hunting and global trade activities. The understanding of the mechanisms of transmission of pathogens to humans allowed the establishment of methods to prevent and control infections. During centuries, implementation of public health measures such as isolation, quarantine and border control helped to contain the spread of infectious diseases and maintain the structure of the society. In the absence of pharmaceutical interventions, these containment methods have still been used nowadays to control COVID-19 pandemic. Global surveillance programs of water-borne pathogens, vector-borne diseases and zoonotic spillovers at the animal-human interface are of prime importance to rapidly detect the emergence of infectious threats. Novel technologies for rapid diagnostic testing, contact tracing, drug repurposing, biomarkers of disease severity as well as new platforms for the development and production of vaccines are needed for an effective response in case of pandemics.
The shift from hunter-gatherers to agrarian societies has favored the spread of infectious diseases in the human population. Expanded trades between communities have increased interactions between humans and animals and facilitated the transmission of zoonotic pathogens.
Pandemics, such as COVID-19, are probably more likely than before. We are with more, we increasingly live in megacities, and we travel vastly more. We also have large quantities of animals for feeding us, where diseases can be created and transferred to us. On the other hand, we have better hygiene, medicine, information, and coordination. But the balance could be negative. Even for diseases originating in nature, the threat level we currently face is largely man-made.
Pandemics such as COVID-19 have a relatively low mortality rate. And even though there are natural pandemics with much higher mortalities, the most prominent existential risk does not come from natural diseases.
The terms endemic, outbreak, epidemic and pandemic relate to the occurrence of a health condition compared to its predicted rate as well as to its spread in geographic areas. An endemic condition occurs at a predictable rate among a population. An outbreak corresponds to an unpredicted increase in the number of people presenting a health condition or in the occurrence of cases in a new area. An epidemic is an outbreak that spreads to larger geographic areas. A pandemic is an epidemic that spreads globally.
Pandemics which are engineered on purpose pose a higher existential risk than natural ones. From the first creation of genetically modified bacteria in 1973, we have steadily increased our ability to create transmissible deadly diseases. The main candidate for existential risk for the next hundred years stems from our technology.
An emerging infection newly appears in a population or is spread in a new geographic area. The zoonotic transmission of pathogens from animals to humans is a pivotal mechanism by which emerging infections have afflicted humans throughout history. The probability of cross-species transmission of pathogens was dramatically enhanced with increased interactions with animals through hunting, animal farming, trade of animal-based foods, wet markets or exotic pet trade. The process of cross-species transmission of pathogens involves 5 different stages. (1) the pathogen exclusively infects animals under natural conditions; (2) the pathogen evolves so that it can be transmitted to humans but without sustained human-to-human transmission; (3) the pathogen undergoes only a few cycles of secondary transmission between humans; (4) the disease exists in animals but long sequences of secondary human-to-human transmission occur without the involvement of animal hosts; and (5) the disease occurs exclusively in humans. The animal species that harbor the pathogen, the nature of human interaction with that animal and the frequency of these interactions likely modulate the risk of zoonotic transmission. Furthermore, land use and climate changes are suggested to play important roles in the transmission of pathogens from wildlife to humans. There is thus a need to implement surveillance programs to rapidly detect the emergence of pathogens with a potential for zoonotic transmission at the animal-human interface.
How has our urban world made pandemics more likely?
For decades, cities have represented many opportunities for a better life; employment and access to health care and education, to name a few. Cities have seen a significant influx from rural areas over the years; in 1950 one-third of the world’s population lived in cities and the rest in rural areas. In the coming decades, this is set to be inverted, with 68% of the global population projected to live in urban areas by 2050.
When the World Health Organization (WHO) declared the novel coronavirus a pandemic in March this year, it issued guidelines on how to reduce transmission. These guidelines include physical distancing, frequent handwashing and self-isolation.
However, for many people living in urban areas in low- and middle-income countries such restrictions often are not feasible or practical to follow. This can be due to a range of factors including: limited access to clean water and sanitation, which makes regular handwashing difficult to achieve; high population density, where large slums with several generations living under a single roof make physical distancing impossible; and a large proportion of the population being dependant on the informal economy. People who rely on informal incomes have no financial safety net from their place of work and cannot self-isolate because they need to provide for themselves and their families.
While these are examples of how urbanization can make responding to a pandemic challenging, urbanization can also increase the likelihood of pandemics. So why do cities provide ideal conditions for infectious diseases to spread?
Population density
Cities are defined by their crowded nature; people living, travelling, working and studying in close quarters means more passive human-to-human contact. This can increase the risk of transmitting viruses. The increased number of passive encounters between people due to high populations and more opportunities for this type of contact to happen due to density can lead to a domino effect in terms of infectivity of viruses and diseases.
Every time an infected person makes contact with another person, they risk exposing those they’ve made contact with to the disease. Moreover, the speed with which diseases can spread in cities can mean that the number of cases rapidly increases, overwhelming the capacity of health systems to manage and respond to disease outbreaks, epidemics and pandemics, which has been the case during the COVID-19 pandemic.
Scale
The size of cities pose challenges to effective infectious disease response. The number of megacities in the world – cities with populations of over ten million people – is increasing. This number of people living in close quarters in itself can create ideal conditions for the spread of infectious diseases.
Megacities such as Delhi, New York City and São Paulo have been heavily affected by COVID-19 with each city reporting most of the confirmed cases in their respective countries. This implies that there may be a direct link between megacities and higher virus transmission rates.
At the start of the pandemic, New York City had a severe outbreak due to its large population. Concerns were raised about sufficient numbers of intensive care unit beds for those severely infected with COVID-19, even though the state has some of the best hospitals in the country. As a back-up plan, ad-hoc intensive care units and field hospitals were set-up but went largely unused as the state shutdown curtailed the spread of the virus.
As people are counted by the millions in cities, ensuring that there is adequate supply of medications and vaccines to treat and prevent diseases can be challenging.
For example, in 2016 Angola experienced the worst yellow fever outbreak the world had seen in 30 years. With most cases occurring in the capital city Luanda, the country managed to vaccinate 5.7 million of the city’s 7 million population against yellow fever using vaccines from the International Coordination Group (ICG) emergency stockpile. However, the stockpile became depleted while they still needed an additional 1.4 million doses just to ensure coverage throughout the capital city, let alone the rest of the country.
To make up for the shortage of vaccines, experts recommended fractional dosing of the yellow fever vaccine, administering one-fifth of a standard dose to provide temporary protection against the disease for at least 12 months. This helped control the outbreak and provide stopgap immunisation coverage to people in Angola and the Democratic Republic of the Congo (DRC), where the outbreak spread from Angola to bordering Kinshasa, DRC’s capital city, and ultimately ended the outbreak.
Slums and informal settlements
Due to ongoing movement of people from rural to urban areas, especially in low- and middle-income countries, affordable and adequate housing is often unavailable. As demand exceeds supply, unplanned slums and informal settlements grow. Since these settlements are overcrowded, poorly ventilated, and lack the infrastructure for adequate water and sanitation, they can put inhabitants at higher risk of infectious diseases.
Cholera and typhoid, for example, are transmitted through food and water contaminated with human faeces containing the pathogen. These diseases are highly prevalent in both rural and urban areas where open defecation is common, but pose an even greater risk where there is overcrowding and shared water sources. Since 2000, global rates of open defecation have reduced by more than half; nevertheless, 673 million people are still without access to adequate toilets according to a recent United Nations report.
In the case of COVID-19, the scarcity of clean water and personal living space has made it nearly impossible for many people to adhere to the preventative measures of frequent handwashing and physical distancing, as recommended by WHO.
Human encroachment
When forests are cleared to make space for residential, commercial and agricultural purposes, habitats of a variety of animals are disturbed or destroyed. These human activities can bring us closer to isolated ecosystems which we wouldn’t necessarily have made contact with in the past, potentially exposing us to new pathogens that normally reside in animals and can then jump to humans.
Zoonotic infections currently account for 60% of reported emerging infectious diseases globally. Primates and bats have consistently been hosts for past viruses which have turned into epidemics and pandemics meaning they can also be vectors of future infectious diseases with pandemic potential. In order to manage this impending threat to global health, we need better understanding, surveillance and prevention of zoonotic diseases.
Urban air bridges
In recent times, aviation has been the fastest growing mode of transportation, enabling people to travel to global destinations in a fraction of the time that it used to. Despite concerns about its impact on climate change, flying remains a popular choice for domestic and international travellers.
However, considering COVID-19 and global lockdown measures, air traffic has seen its sharpest decline since 9/11. According to The International Air Transport Association (IATA) passenger demand in May 2020 dropped by 91.3% compared to May 2019.
Air travel has not only enhanced the interconnectedness of our world but has also accelerated the transmission of viruses and infectious diseases between cities. It is possible to travel from Nairobi to London to New York in less time it takes for a virus to incubate, meaning that air travel makes it possible for a virus to move across the globe quickly and undetected.
Moreover, many international airports in the world’s largest cities, such as London Heathrow, John F. Kennedy International Airport in New York and Dubai International Airport see tens of millions of passengers passing through each year. And besides the sheer number of people making indirect contact in airports, passengers can be in planes for hours on end inhaling tiny droplets created by people coughing and sneezing before the air has been filtered. During the 2003 severe acute respiratory syndrome (SARS) outbreak, 22 people were diagnosed with confirmed or probable cases of SARS after sitting within 7 rows of an elderly man who later died of atypical pneumonia a few days after the flight.
Before the COVID-19 pandemic, the number of international air travellers had doubled since after the SARS outbreak ended in 2003. This increase in global interconnectivity, combined with the growth of urbanisation and relentless human encroachment on natural habitats, is making it increasingly easier for viruses to spread.
Climate changes also influence the transmission of pathogens (e.g., Dengue, Chikungunya, Zika, Japanese encephalitis, West Nile viruses, Borrelia burgdorferi) by expanding the habitats of various common zoonotic disease-carrying vectors (e.g., Aedes albopictus mosquitos, ticks). The emergence of vector-borne pathogens in non-endemic regions often results in explosive epidemics. Land use due to increasing human population also affects the distribution of disease-carrying vectors. Control of vector-borne zoonotic pathogens usually requires vector control to reverse the drivers of transmission.
Furthermore, the spread of several infectious diseases (e.g., tuberculosis, malaria, cholera) to extended geographic areas are now raising health concerns for a significant proportion of the population. These diseases show a wider spread as a result of the acquisition of drug resistance, tolerance of mosquito vector to insecticides, poor sanitation, land use and climate changes as well as increased in human mobility and travels. Furthermore, outbreaks of cholera in regions where natural disasters occurred such as earthquakes and floods were also reported. Surveillance programs should be also implemented to control the spread of these pathogens from endemic to non-endemic regions.
Finally, infectious agents (e.g., Bacillus anthracis, Yersinia pestis, variola virus) could be used as bioweapons and could thus constitute threats for humanity. These weapons are based on natural microorganisms or microorganisms that are engineered to be more virulent, highly transmissible or resistant to therapy. The release of these biological weapons is intended to induce diseases in humans or even death. Therefore, governments should establish biowarfare, bioterrorism and biocrime preparedness plans to protect the population.
However, the legacy of COVID-19 may impact where we choose to live; what once was a rural-urban migration may reverse over time if people favour less crowded living situations, possibly in the countryside. In the meantime, ‘smart’ urban planning to reduce overcrowding and increased access to health and preventive interventions like vaccines can protect the most vulnerable, and reduce the likelihood and spread of pandemics in the years to come.
Nature-based or lab leak? Unraveling the debate over the origins of COVID-19
Accomplished scientists and public health officials stand on both sides.
An accidental lab leak, or the dark side of mother nature?
That fundamental question — about the origins of a COVID-19 pandemic that has taken nearly 4 million lives — has sparked a political firestorm in the U.S. and threatened the already fraught ties between Washington and Beijing.
So far, multiple investigations have yielded few definitive conclusions. And as infection rates and deaths tail off in many developed countries, the Chinese government’s perceived lack of cooperation into those investigations has prompted some of the world’s leading virologists to reconsider the possibility that this pandemic could have been caused by a lab accident.
In the early days of the pandemic, experts largely felt that the most likely explanation was that the virus jumped directly from animals to humans — like all other pandemics and epidemics have in the past. Attention turned to a closely quartered wet-market in the central Chinese hub of Wuhan, freshly scrutinized for the exotic wild fare, which offered ample opportunity for an intermediary host. But while environmental samples from the market came back positive for the virus, animal samples that were tested ultimately did not.
Conservative political leaders in the U.S. have long seized on an alternative explanation for the virus’ spread, some insinuating that the virus could have been engineered as a weapon at a famous coronavirus research center in Wuhan.
With no proof available, accomplished scientists and public health officials stand on both sides of the debate. But all parties agree on the stakes: Uncovering the truth could help prevent the next global pandemic.
Now, at the behest of President Joe Biden, the U.S. intelligence community is scrambling to deliver answers, prompted by the depth of the potential evidence still untapped — and despite concerns that the answers may never be found.
Key clues, a decade in the making
To understand more about SARS-CoV-2, the virus that causes COVID-19, experts look back nearly a decade — to an abandoned copper mine in southwestern China. In 2012, a team of miners cleaning out bat excrement fell ill with respiratory illnesses. Three ultimately died.
Researchers from the Wuhan Institute of Virology flocked to the site, where they “sampled the viruses that were found in those bat droppings in those caves, and brought them back to their lab,” explained David Feith, a former State Department official who helped investigate the origins of COVID-19.
One of the viruses that researchers retrieved from the mines and brought back to their lab in Wuhan is about 96% similar almost identical to SARS-COV-2 — a point that advocates of the lab-leak theory have highlighted as crucial evidence.
Virologists say that 96% similar virus is a cousin — not a twin — of SARS-CoV-2. But its existence reveals that scientists at Wuhan Institute of Virology could have been within striking distance of discovering the virus that ultimately caused the pandemic.
“Of all the places in the world where there could be a natural outbreak from transmission, from an intermediary host in the wild, what are the chances that that would … happen in Wuhan, the town with the only level-4 virology institute in all of China?” said Jamie Metzl, an adviser to the World Health Organization and former national security official in the Clinton administration.
The Chinese government and leaders at the Wuhan Institute of Virology have vehemently denied that the virus came from their lab.
Chinese Foreign Ministry spokesperson Zhao Lijian responded to the rekindled interest in investigating the lab-leak theory in late May, accusing the Biden administration of playing politics and shirking its own responsibility, and saying Biden’s order showed that the U.S. “does not care about facts and truth, nor is it interested in serious scientific origin tracing.”
Metzl and other lab-leak theory advocates have pushed for further investigation, and the need to determine whether Wuhan scientists working on the coronaviruses may have inadvertently contracted the disease and spread it to the community.
The possibility of such a leak was a distinct possibility, even to Shi Zhengli, a lead researcher in the Wuhan facility who is colloquially known as “Bat Woman” because of her decades-long research of coronaviruses. Shi told Scientific American last year that when the COVID19 virus first emerged in Wuhan, she remembered wondering, “Could they have come from our lab?”
After testing the novel coronavirus’ viral genomes, Shi said her team determined that they did not match any samples from the lab, and dismissed the premise.
“That really took a load off my mind,” Shi told Scientific American. “I had not slept a wink for days.”
Early in the pandemic, the then-president and his allies sought to shift blame for the poor U.S. response toward China — seeking to re-brand the coronavirus as the “China Virus” or the “Kung Flu.” With Trump weaponizing accusations of a lab leak, even some within his administration recognized it could undermine solid evidence supporting that theory.
“There was so little space, even for Democrats, even for progressives, to ask the questions,” said Metzl.
In February 2020, a group of 27 prominent scientists penned a forceful letter in The Lancet condemning any “conspiracy theories suggesting that COVID-19 does not have a natural origin.”
Several leading virologists argued that if the disease had been explicitly engineered in a lab, there would be evidence of that in its genomic sequence. But because there is no such evidence, “the weight of probability would very, very, very strongly indicate that this was a natural event,” said Dennis Carroll, chairman of the Global Virome Project and a signatory of The Lancet letter.
A World Health Organization-led team that visited Wuhan in January of this year released their long-awaited findings in March, echoing a similar stance: A lab leak was “extremely unlikely,” the report said, and determined that animal-to-human transmission through an intermediary host remained a more plausible explanation. But ultimately, the team ruled nothing out.
“Most likely the origin of SARS-CoV-2 is going to be linked to this large wildlife trade,” said Robert Garry, a virologist at Tulane University. “And we know that there are many farms and other sources of these animals that are trapped in the wild and brought to big cities like Wuhan and then distributed to other places.”
In fact, newly published data shows just how often wildlife is bought and sold in China, with researchers recently documenting the trafficking of 38 wildlife species and more than 40,000 individual animals in Wuhan’s markets from May 2017 to November 2019.
But as Garry readily concedes, scientists haven’t yet found that animal host — a gap in the narrative that has emboldened some lab-leak theorists. Researchers still have yet to identify an animal source, which Garry said “could take years.”
Further complicating matters: The director of the Chinese CDC has also said that samples taken from animals at the wet-market tested negative for the virus, meaning finding the natural host could prove more elusive than initially expected.
The void of definitive evidence has prompted calls among some, including former high-ranking members of the Trump administration, to question the virus’ natural origins — and to continue investigating.
“Everybody got into this groupthink,” said Metzl, “and that was the story.”
New evidence supporting lab-leak theory?
Among the circumstantial evidence that could support the lab-leak theory, some researchers have pointed to the fact that the Wuhan Institute of Virology has in the past conducted a controversial type of scientific research called gain-of-function.
“They were doing what some people have called gain-of-function research — seeing how the world’s scariest viruses might infect human cells,” Metzl said.
Gain-of-function research is a technique used by scientists to enhance aspects of an organism. It is common in some fields as a means to study genetic variations and better understand biological entities — but its use in certain settings to enhance the lethality or transmissibility of a virus has become controversial.
“The idea was, ‘Let’s understand these viruses so we know what we’re facing,'” Metzl said. “The counterargument was, we’re playing with fire. If it turns out that COVID-19 stems from an accidental lab incident from the Wuhan Institute of Virology or the Wuhan CDC, it will turn out that that fear was certainly well-founded.”
The fear that researchers’ work within the lab could be tied to the pandemic was bolstered in April 2020 when the Washington Post reported that U.S. embassy officials who visited the Wuhan Institute of Virology in recent years sent two cables back to Washington about “inadequate safety at the lab” tied to its gain-of-function research on bat coronaviruses.
Then, in January 2021, a State Department report revealed that several Wuhan Institute of Virology researchers fell ill in the fall of 2019 with “symptoms consistent with both COVID-19 and common seasonal illnesses” — though it’s not clear if they had COVID-19, the flu, or possibly another illness. ABC News confirmed from a separate U.S. intelligence report that three researchers sought hospital treatment in November of 2019.
Shi Zhengli insists that she tested all her workers for COVID-19 antibodies, and all tests came back negative.
David Asher, a former U.S. official who led the State Department’s probe into the coronavirus’ origins, said China’s refusal to allow access to American investigators suggests it had something to hide.
“We’re talking lights out. There was no cooperation and there still is no cooperation,” Asher said. “So the cover-up could be worse than the crime if the crime wasn’t really suspiciously horrible.”
ABC News also reported in June 2020 that satellite images showed dramatic spikes in auto traffic around major hospitals in Wuhan in the fall of 2019, suggesting the novel coronavirus may have been present before the outbreak was first reported to the world.
Meanwhile, ABC News reached out to all 27 of the scientists who penned the February 2020 letter “denouncing conspiracy theories suggesting that COVID-19 does not have a natural origin.” Of the 12 who replied, one now believes a lab leak is more likely and five more said a lab leak should not be ignored as a possibility. Four others stood by their stance in the letter, and another called for a complete and thorough investigation.
Dr. Charles Calisher, a Colorado State University virologist and the lone signatory to completely change his position, told ABC News that he now believes that “there is too much coincidence” to ignore the lab-leak theory and that “it is more likely that it came out of that lab.”
In addition to the circumstantial evidence pointing to a possible lab leak, allegations that the Chinese government has not been transparent has weighed on the minds of those seeking to examine all possible explanations.
Marion Koopmans, a Dutch virologist who traveled with the WHO to Wuhan for their investigation, said the Chinese government cooperated to an extent, but said “it was not so easy” to gather information.
“Was everything you would wish to see on the table? No,” she said.
For U.S. government investigators, “interest spiked considerably in March of 2020 because we were dealing with the very concerning problems of the Chinese government’s cover-up of what was happening in Wuhan,” said Feith, the former State Department official under President Trump.
“We were concerned that they were not accepting U.S. offers of help that would have involved U.S. scientists and other international scientists getting in on the ground to be able to learn things,” Feith said. “We were concerned that the information that the Chinese authorities were giving to the outside world through the press and through the World Health Organization was unreliable– and might have been deliberately misleading.”
After the WHO released its March report casting doubt on the lab-leak theory, the organization’s chief, Tedros Adhanom Ghebreyesus, said gaps in their probe merited further investigation, and that the team had “expressed the difficulties they encountered in accessing raw data.”
“I do not believe that this assessment was extensive enough,” Ghebreyesus said. “Further data and studies will be needed to reach more robust conclusions.”
“As I have said,” he added, “all hypotheses remain on the table.”
“It’s important to stay open-minded, because we don’t know exactly what happened,” said Koopmans. “We are scratching the surface — and it’s important that we learn and collaborate to learn from these outbreaks.”
Scientific consensus or dangerous groupthink?
Despite some fringe skepticism — often emanating from voices with a long record of criticizing China — the idea that COVID-19 jumped from animal to human somewhere in nature became the overwhelming consensus. Political voices in favor of the lab-leak theory, particularly from President Donald Trump, served to polarize the issue further and largely pushed the scientific community away from a willingness to consider the lab-leak theory.
The pandemic highlights the man-made disasters to come.
Now that the COVID-19 pandemic has fully arrived, how bad it gets will largely be a function of how our society responds at every level.
Why it matters: From pandemics to climate change to earthquakes, massive catastrophes lie in our future. But in a world that has the technological capability that ours does, we have the power to mitigate those disasters through our preparation and resilience — or to make them worse through our failures.
Today we can either directly see through technology a disaster coming or reasonably know our level of risk based on the experience of the past or the ability to model what’s to come.
What this means is that in the truest sense, no disaster is really — or only — natural. The toll a catastrophe takes, especially in human lives, now has as much or more to do with our preparation, response and level of wealth as it has to do with the strength of the event itself.
–One example: The 2010 earthquake that hit Haiti had a 7.0 magnitude and killed at least 220,000 people, while another temblor that struck a much better prepared Chile a month later was far stronger, yet killed fewer than 600 people.
–The COVID-19 pandemic was entirely foreseeable, as I reported recently.
-Yet by refusing to take that threat seriously, and even dismantling some of the response measures that were already in place, the U.S. effectively expanded its “bull’s-eye of risk” for an infectious disease disaster.
Be smart: What happens next with COVID-19 will have far more to do with the steps we take in the days and weeks ahead than anything to do with the virus itself.
-The New York Times reported on March 13 that worst-case projections by the CDC had as many as 214 million Americans being infected and as many as 1.7 million dying.
-But those projections assume that nothing would be done to slow the spread of the novel coronavirus. The wide-scale canceling of social gatherings and distancing measures being put in place will almost surely bend that curve.
-The apparent success of China and South Korea in curbing the outbreak, and places like Hong Kong and Singapore in preventing the disease from gaining a strong foothold in the first place, demonstrates the difference that action can make.
What’s true of the pandemic now will also be true of threats from megatrends that will only intensify in the future, like climate change. What we do to directly mitigate global warming and adapt to its effects will determine our level of risk.
-Actions that make us more vulnerable — like building up development on coastlines that face rising seas or allowing vaccination rates for preventable diseases to fall — expand the bull’s-eye of risk.
-Mismanagement of a disaster while it occurs or immediately after it can make a catastrophe far worse, as we saw with Hurricane Katrina in 2005.
The bottom line: There’s no such thing as a natural disaster anymore. Our ability to prepare and respond to what nature throws at us is our strength — or, should we fail to do both, our vulnerability.
Resources
existentialriskobservatory.org, ” Man-made pandemics.”; gavi.org, “How has our urban world made pandemics more likely? As more people have moved to cities, population density, human encroachment and increased global interconnectivity have contributed to the spread of infectious diseases.” By Gavii Staff; frontiersin.org, “Pandemics Throughout History.” By Jocelyn Piret and Guy Boivin; abcnews.com, “Nature-based or lab leak? Unraveling the debate over the origins of COVID-19: Accomplished scientists and public health officials stand on both sides.” By Kaitlyn Folmer, Sony Salzman, Sasha Pezenik, Dr. Mark Abdelmalek, and Lucien Bruggeman; axios.com, “The pandemic highlights the man-made disasters to come.” By Bryan Walsh;