Rising temperatures in the Arctic are melting the glacial ice, a frozen layer of earth beneath the surface, and could potentially stir up viruses that, after laying dormant for tens of thousands of years, could damage animal and human health.
While the idea of a pandemic being started by a disease from the past sounds like the premise of a science fiction film, scientists warn that the risks, albeit modest, are not being taken seriously enough. Thaws can also result in the release of Cold War-era radioactive and chemical waste that could harm species and disturb ecosystems.
Keeping as much of the permafrost frozen as possible is crucial, according to Kimberley Miner, a climate scientist at the NASA Jet Propulsion Laboratory at the California Institute of Technology in Pasadena, California. “There’s a lot going on with the permafrost that is of concern.”
Permafrost
A fifth of the Northern Hemisphere is covered in permafrost, which has long supported the Arctic tundra and boreal forests of Alaska, Canada, and Russia. Together with ancient viruses, it acts as a kind of time capsule, preserving the mummified remains of several extinct creatures, including two cave lion cubs and a woolly rhino, that scientists have recently been able to find and examine.
Not only is permafrost cold, but it also lacks oxygen and is opaque to light, making it an ideal storage medium. Yet, the Arctic is currently warming up to four times faster than the rest of the world, which is undermining the region’s top layer of permafrost.
Jean-Michel Claverie, an emeritus professor of medicine and genomics at the Aix-Marseille University School of Medicine in Marseille, France, has examined earth samples taken from Siberian permafrost to determine if any viral particles contained therein are still infectious in order to better understand the dangers posed by frozen viruses. He’s looking for what he calls “zombie viruses,” and he’s found some of them.
The virologists Who Discovered The Zombie Virus
Claverie researches a specific viral subtype that he initially identified in 2003. Giant viruses are a useful example for this kind of lab work since they are larger than the ordinary kind and can be seen with a standard light microscope rather than a more potent electron microscope.
He was somewhat motivated in his search for viruses encased in permafrost by a group of Russian scientists who in 2012 regenerated a wildflower from 30,000-year-old seed tissue discovered in a squirrel’s tunnel. Since then, researchers have also been successful in reviving ancient microscopic organisms.
He and his colleagues discovered a virus under the permafrost, and in 2014, he was able to bring it back to life by reintroducing it into cultivated cells, making it contagious for the first time in 30,000 years. He had selected to research a virus that could only infect single-celled amoebas—not animals or people—for safety’s sake.
Earlier Discoveries
In 2015, he accomplished the same feat again by discovering a new viral kind that also affected amoebas. And in his most recent study, which was released on February 18 in the journal Viruses, Claverie and his team isolated a number of ancient virus strains from permafrost samples collected from seven different locations across Siberia, and they demonstrated that each one was capable of infecting cultured amoeba cells.
In addition to the two viral families he earlier restored, those most recent strains constitute five additional virus families. The oldest was found in soil that was retrieved from an underground lake that was 16 meters (52 feet) below the surface and was radiocarbon dated to be over 48,500 years old. The youngest samples were 27,000 years old and were discovered in the gut and coat of a woolly mammoth’s remnants.
The fact that amoeba-infecting viruses are still contagious after all this time suggests a broader issue, according to Claverie. He worries that people won’t take his work seriously and won’t see the possibility of extinct diseases resurfacing as a serious threat to public health.
He continued, “We see the remains of many, many, many additional viruses. “We are aware that they exist. The fact that they are still alive is uncertain. Yet if the amoeba viruses are still alive, then there is no reason why the other viruses should not still be alive and able to infect their own hosts, according to our logic.
A history of human infection
Permafrost has been discovered to contain remnants of bacteria and viruses that can harm people.
The genome of the influenza strain that caused the 1918 pandemic was found in the lungs of a lady whose body was unearthed from permafrost in a town on the Seward Peninsula of Alaska in 1997. In 2012, it was determined by experts that the 300-year-old mummified bones of a lady buried in Siberia had the genetic markers for the smallpox virus.
The deeper thawing of the permafrost during exceptionally hot summers has also been linked to an anthrax outbreak in Siberia that affected dozens of people and more than 2,000 reindeer between July and August of 2016. This allowed old Bacillus anthracis spores to resurface from old burial grounds or animal carcasses.
Better monitoring of the risk posed by possible pathogens in thawing permafrost is necessary, but Birgitta Evengrd, professor emerita at Umea University’s Department of Clinical Microbiology in Sweden, cautioned against taking an overly alarmist attitude.
The CLINF Nordic Centre of Excellence is a group that studies the effects of climate change on the occurrence of infectious diseases in people and animals in northern regions. “You must remember our immune system has been developed in close contact with microbiological environment,” stated Evengrd.
“Our immune protection may not be adequate if there is a virus hiding in the permafrost that we have not been exposed to for thousands of years,” she warned. “Respecting the circumstances and acting pro-actively rather than just reactively are appropriate. Because knowledge is the best weapon against fear.
Chances of viral spillover Of Zombie Virus
Naturally, in the real world, scientists are unsure of the length of time that the zombie virus could remain contagious after being exposed to the current environment or the likelihood that they would come into contact with a compatible host. Some viruses are benign or even helpful to their hosts, meaning they are not all pathogens that can inflict disease. Although there are 3.6 million people living there, the Arctic is still a sparsely inhabited region, therefore there is very little chance that anyone may come into contact with old diseases.
However, Claverie noted that because of global warming, “the risk is bound to increase,” since permafrost thawing will continue to speed up and more people will move to the Arctic as a result of industrial endeavors.
Claverie isn’t the only person to warn that the area would be ripe for a spillover event, which occurs when a virus infects a new host and begins to spread.
Research on soil and lake sediment samples from Lake Hazen, a freshwater lake in Canada near the Arctic Circle, was released last year by a group of experts. Scientists sequenced the genetic material in the sand to discover viral signals and the genomes of potential hosts — plants and animals — in the vicinity.
The probability of viruses spreading to new hosts was shown to be higher in areas close to where significant amounts of glacial meltwater flowed into lakes. Which is a situation that grows more probable as the climate warms.
unknown effects Of The Zombie Virus
The first step in figuring out what risk viruses and other dangers present to the Arctic. According to Miner at NASA’s Jet Propulsion Laboratory, is to identify what dangers are present in the warming permafrost. Quantifying when, where, how quickly, and how deeply permafrost will thaw are further difficulties.
In some cases, such as in the case of significant land slumps that might unexpectedly reveal deep and ancient layers of permafrost, thawing can occur more quickly than millimeters per decade. Methane and carbon dioxide are also released during the process, contributing to climate change in a hidden and underappreciated way.
In a report that was published in the scientific journal Nature Climate Change in 2021, Miner compiled a variety of potential dangers that are currently encased in Arctic permafrost.
Effect Of The Zombie Virus
These potential risks included buried waste from heavy metal and chemical mining. Including the insecticide DDT, which was outlawed in the early 2000s. With the start of nuclear testing in the 1950s, radioactive material has also been deposited in the Arctic by both Russia and the United States.
“Abrupt thaw rapidly exposes old permafrost horizons. Releasing chemicals and microbes hidden in deeper levels,” Miner and other scientists said in the 2021 publication.
According to Miner’s research article, it is “currently doubtful” that zombie virus discharged from permafrost will directly infect humans.
But Miner expressed concern over what she called “Methuselah microbes” (named after the Biblical figure with the longest life span). These species have the potential to introduce the dynamics of old and extinct ecosystems into the modern Arctic, with unknowable repercussions.
According to Miner, the re-emergence of ancient bacteria (zombie virus) could alter soil composition and vegetative development. Perhaps exacerbating the effects of climate change.
We don’t really know how these bacteria will interact with the contemporary environment, she said. “I don’t think any of us really want to run that experiment,”
According to Miner, the best course of action is to try to stop the thaw and the larger climate catastrophe. And keep these dangers permanently buried in the permafrost.
Via CNN