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‘Zombie’ virus spent 48,500 years in permafrost: scientists

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Warmer temperatures in the Arctic are thawing the region’s permafrost — a frozen layer of soil beneath the ground — and potentially stirring viruses that, after lying dormant for tens of thousands of years, could endanger animal and human health.

While a pandemic unleashed by a disease from the distant past sounds like the plot of a sci-fi movie, scientists warn that the risks, though low, are underappreciated. Chemical and radioactive waste that dates back to the Cold War, which has the potential to harm wildlife and disrupt ecosystems, may also be released during thaws.

“There’s a lot going on with the permafrost that is of concern, and (it) really shows why it’s super important that we keep as much of the permafrost frozen as possible,” said Kimberley Miner, a climate scientist at the NASA Jet Propulsion Laboratory at the California Institute of Technology in Pasadena, California.

Permafrost covers a fifth of the Northern Hemisphere, having underpinned the Arctic tundra and boreal forests of Alaska, Canada and Russia for millennia. It serves as a kind of time capsule, preserving — in addition to ancient viruses — the mummified remains of a number of extinct animals that scientist have been able to unearth and study in recent years, including two cave lion cubs and a woolly rhino.

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The reason permafrost is a good storage medium isn’t just because it’s cold; it’s an oxygen-free environment that light doesn’t penetrate. But current day Arctic temperatures are warming up to four times faster than the rest of the planet, weakening the top layer of permafrost in the region.

To better understand the risks posed by frozen viruses, Jean-Michel Claverie, an Emeritus professor of medicine and genomics at the Aix-Marseille University School of Medicine in Marseille, France, has tested earth samples taken from Siberian permafrost to see whether any viral particles contained therein are still infectious. He’s in search of what he describes as “zombie viruses” — and he has found some.

THE VIRUS HUNTER

Claverie studies a particular type of virus he first discovered in 2003. Known as giant viruses, they are much bigger than the typical variety and visible under a regular light microscope, rather than a more powerful electron microscope — which makes them a good model for this type of lab work.

His efforts to detect viruses frozen in permafrost were partly inspired by a team of Russian scientists who in 2012 revived a wildflower from a 30,000-year-old seed tissue found in a squirrel’s burrow. (Since then, scientists have also successfully brought ancient microscopic animals back to life.)

In 2014, he managed to revive a virus he and his team isolated from the permafrost, making it infectious for the first time in 30,000 years by inserting it into cultured cells. For safety, he’d chosen to study a virus that could only target single-celled amoebas, not animals or humans.

He repeated the feat in 2015, isolating a different virus type that also targeted amoebas. And in his latest research, published February 18 in the journal Viruses, Claverie and his team isolated several strains of ancient virus from multiple samples of permafrost taken from seven different places across Siberia and showed they could each infect cultured amoeba cells.

Those latest strains represent five new families of viruses, on top of the two he had revived previously. The oldest was almost 48,500 years old, based on radiocarbon dating of the soil, and came from a sample of earth taken from an underground lake 16 meters (52 feet) below the surface. The youngest samples, found in the stomach contents and coat of a woolly mammoth’s remains, were 27,000 years old.

That amoeba-infecting viruses are still infectious after so long is indicative of a potentially bigger problem, Claverie said. He fears people regard his research as a scientific curiosity and don’t perceive the prospect of ancient viruses coming back to life as a serious public health threat.

“We view these amoeba-infecting viruses as surrogates for all other possible viruses that might be in the permafrost,” Claverie told CNN.

“We see the traces of many, many, many other viruses,” he added. “So we know they are there. We don’t know for sure that they are still alive. But our reasoning is that if the amoeba viruses are still alive, there is no reason why the other viruses will not be still alive, and capable of infecting their own hosts.”

PRECEDENT FOR HUMAN INFECTION

Traces of viruses and bacteria that can infect humans have been found preserved in permafrost.

lung sample from a woman’s body exhumed in 1997 from permafrost in a village on the Seward Peninsula of Alaska contained genomic material from the influenza strain responsible for the 1918 pandemic. In 2012, scientists confirmed the 300-year-old mummified remains of a woman buried in Siberia contained the genetic signatures of the virus that causes smallpox.

An anthrax outbreak in Siberia that affected dozens of humans and more than 2,000 reindeer between July and August in 2016 has also been linked to the deeper thawing of the permafrost during exceptionally hot summers, allowing old spores of Bacillus anthracis to resurface from old burial grounds or animal carcasses.

Birgitta Evengård, professor emerita at Umea University’s Department of Clinical Microbiology in Sweden, said there should be better surveillance of the risk posed by potential pathogens in thawing permafrost, but warned against an alarmist approach.

“You must remember our immune defence has been developed in close contact with microbiological surroundings,” said Evengård, who is part of the CLINF Nordic Centre of Excellence, a group that investigates the effects of climate change on the prevalence of infectious diseases in humans and animals in northern regions.

“If there is a virus hidden in the permafrost that we have not been in contact with for thousands of years, it might be that our immune defence is not sufficient,” she said. “It is correct to have respect for the situation and be proactive and not just reactive. And the way to fight fear is to have knowledge.”

CHANCES OF VIRAL SPILLOVER

Of course, in the real world, scientists don’t know how long these viruses could remain infectious once exposed to present-day conditions, or how likely the virus would be to encounter a suitable host. Not all viruses are pathogens that can cause disease; some are benign or even beneficial to their hosts. And while it is home to 3.6 million people, the Arctic is still a sparsely populated place, making the risk of human exposure to ancient viruses very low.

Still, “the risk is bound to increase in the context of global warming,” Claverie said, “in which permafrost thawing will keep accelerating, and more people will populate the Arctic in the wake of industrial ventures.”

And Claverie isn’t alone in warning that the region could become a fertile ground for a spillover event — when a virus jumps into a new host and starts to spread.

Last year, a team of scientists published research on samples of soil and lake sediment taken from Lake Hazen, a freshwater lake in Canada located within the Arctic circle. They sequenced the genetic material in the sediment to identify viral signatures and the genomes of potential hosts — plants and animals — in the area.

Using a computer model analysis, they suggested the risk of viruses spilling over to new hosts was higher at locations close to where large amounts of glacial meltwater flowed into the lake — a scenario that becomes more likely as the climate warms.

UNKNOWN CONSEQUENCES

Identifying viruses and other hazards contained in the warming permafrost is the first step in understanding what risk they pose to the Arctic, Miner at NASA’s Jet Propulsion Laboratory said. Other challenges include quantifying where, when, how fast and how deep permafrost will thaw.

Thawing can be a gradual process of as little as centimetres per decade, but also happens more rapidly, such as in the case of massive land slumps that can suddenly expose deep and ancient layers of permafrost. The process also releases methane and carbon dioxide into the atmosphere — an overlooked and underestimated driver of climate change.

Miner catalogued an array of potential hazards currently frozen in Arctic permafrost in a 2021 paper published in the scientific journal Nature Climate Change.

Those possible dangers included buried waste from the mining of heavy metals and chemicals such as the pesticide DDT, which was banned in the early 2000s. Radioactive material has also been dumped in the Arctic — by Russia and the United States — since the advent of nuclear testing in the 1950s.

“Abrupt thaw rapidly exposes old permafrost horizons, releasing compounds and microorganisms sequestered in deeper layers,” Miner and other researchers noted in the 2021 paper.

In the research paper, Miner labelled the direct infection of humans with ancient pathogens released from permafrost as “currently improbable.”

However, Miner said she is worried about what she termed “Methuselah microorganisms” (named after the Biblical figure with the longest life span). These are organisms that could bring the dynamics of ancient and extinct ecosystems into the present-day Arctic, with unknown consequences.

The re-emergence of ancient microorganisms has the potential to change soil composition and vegetative growth, possibly further accelerating the effects of climate change, Miner said.

“We’re really unclear as to how these microbes are going to interact with the modern environment,” she said. “It’s not really an experiment that I think any of us want to run.”

The best course of action, Miner said, is to try and halt the thaw, and the wider climate crisis, and keep these hazards entombed in the permafrost for good.

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NASA to launch sounding rockets into moon's shadow during solar eclipse – Phys.org

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This photo shows the three APEP sounding rockets and the support team after successful assembly. The team lead, Aroh Barjatya, is at the top center, standing next to the guardrails on the second floor. Credit: NASA/Berit Bland

NASA will launch three sounding rockets during the total solar eclipse on April 8, 2024, to study how Earth’s upper atmosphere is affected when sunlight momentarily dims over a portion of the planet.

The Atmospheric Perturbations around Eclipse Path (APEP) sounding rockets will launch from NASA’s Wallops Flight Facility in Virginia to study the disturbances in the created when the moon eclipses the sun. The sounding rockets had been previously launched and successfully recovered from White Sands Test Facility in New Mexico, during the October 2023 .

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They have been refurbished with new instrumentation and will be relaunched in April 2024. The mission is led by Aroh Barjatya, a professor of engineering physics at Embry-Riddle Aeronautical University in Florida, where he directs the Space and Atmospheric Instrumentation Lab.

The sounding rockets will launch at three different times: 45 minutes before, during, and 45 minutes after the peak local eclipse. These intervals are important to collect data on how the sun’s sudden disappearance affects the ionosphere, creating disturbances that have the potential to interfere with our communications.

The ionosphere is a region of Earth’s atmosphere that is between 55 to 310 miles (90 to 500 kilometers) above the ground. “It’s an electrified region that reflects and refracts and also impacts as the signals pass through,” said Barjatya. “Understanding the ionosphere and developing models to help us predict disturbances is crucial to making sure our increasingly communication-dependent world operates smoothly.”

A sounding rocket is able to carry science instruments between 30 and 300 miles above Earth’s surface. These altitudes are typically too high for science balloons and too low for satellites to access safely, making sounding rockets the only platforms that can carry out direct measurements in these regions. Credit: NASA’s Goddard Space Flight Center

The ionosphere forms the boundary between Earth’s lower atmosphere—where we live and breathe—and the vacuum of space. It is made up of a sea of particles that become ionized, or electrically charged, from the sun’s energy or .

When night falls, the ionosphere thins out as previously ionized particles relax and recombine back into neutral particles. However, Earth’s terrestrial weather and space weather can impact these particles, making it a dynamic region and difficult to know what the ionosphere will be like at a given time.

It’s often difficult to study short-term changes in the ionosphere during an eclipse with satellites because they may not be at the right place or time to cross the eclipse path. Since the exact date and times of the are known, NASA can launch targeted sounding rockets to study the effects of the eclipse at the right time and at all altitudes of the ionosphere.

As the eclipse shadow races through the atmosphere, it creates a rapid, localized sunset that triggers large-scale atmospheric waves and small-scale disturbances or perturbations. These perturbations affect different radio communication frequencies. Gathering the data on these perturbations will help scientists validate and improve current models that help predict potential disturbances to our communications, especially high-frequency communication.

This conceptual animation is an example of what observers might expect to see during a total solar eclipse, like the one happening over the United States on April 8, 2024. Credit: NASA’s Scientific Visualization Studio

The APEP rockets are expected to reach a maximum altitude of 260 miles (420 kilometers). Each rocket will measure charged and neutral particle density and surrounding electric and magnetic fields. “Each rocket will eject four secondary instruments the size of a two-liter soda bottle that also measure the same data points, so it’s similar to results from fifteen rockets while only launching three,” explained Barjatya. Embry-Riddle built three secondary instruments on each rocket, and the fourth one was built at Dartmouth College in New Hampshire.

In addition to the rockets, several teams across the U.S. will also be taking measurements of the ionosphere by various means. A team of students from Embry-Riddle will deploy a series of high-altitude balloons. Co-investigators from the Massachusetts Institute of Technology’s Haystack Observatory in Massachusetts and the Air Force Research Laboratory in New Mexico will operate a variety of ground-based radars taking measurements.

Using this data, a team of scientists from Embry-Riddle and Johns Hopkins University Applied Physics Laboratory are refining existing models. Together, these various investigations will help provide the puzzle pieces needed to see the bigger picture of ionospheric dynamics.

The animation depicts the waves created by ionized particles during the 2017 total solar eclipse. Credit: MIT Haystack Observatory/Shun-rong Zhang. Zhang, S.-R., Erickson, P. J., Goncharenko, L. P., Coster, A. J., Rideout, W. & Vierinen, J. (2017). Ionospheric Bow Waves and Perturbations Induced by the 21 August 2017 Solar Eclipse. Geophysical Research Letters, 44(24), 12,067-12,073. https://doi.org/10.1002/2017GL076054

When the APEP- launched during the 2023 annular solar eclipse, scientists saw a sharp reduction in the density of charged particles as the annular eclipse shadow passed over the atmosphere.

“We saw the perturbations capable of affecting radio communications in the second and third rockets, but not during the first rocket that was before peak local eclipse,” said Barjatya. “We are super excited to relaunch them during the total eclipse to see if the perturbations start at the same altitude and if their magnitude and scale remain the same.”

The next total solar eclipse over the contiguous U.S. is not until 2044, so these experiments are a rare opportunity for scientists to collect crucial data.

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Royal Sask. Museum research finds insect changes may have set stage for dinosaurs' extinction – CTV News Regina

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Research by the Royal Saskatchewan Museum (RSM) shows that ecological changes were occurring in insects at least a million years before dinosaur extinction.

Papers published in the scientific journal, Current Biology, describe the first insect fossils found in amber from Saskatchewan and the unearthing of three new ant species from an amber deposit in North Carolina, according to a release from the province.

The amber deposit from in the Big Muddy Badlands of Saskatchewan, which was formed about 67 million years ago, preserved insects that lived in a swampy redwood forest about one million years before the extinction of dinosaurs.

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“Fossils in the amber deposit seem to show that common Cretaceous insects may have been replaced on the landscape by their more modern relatives, particularly in groups such as ants, before the extinction event,” Elyssa Loewen, curatorial assistant, said.

The research team was led by Loewen and Dr. Ryan McKellar, the RSM’s curator of paleontology.

“These new fossil records are closer than anyone has gotten to sampling a diverse set of insects near the extinction event, and they help researchers fill in a 17-million-year gap in the fossil record of insects around that time,” Dr. McKellar said.

The three ant species discovered in North Carolina also belonged to extinct groups that didn’t survive past the Cretaceous period.

“When combined with the work in Saskatchewan, the two recent papers show that there was a dramatic change in ant diversity sometime between 77 and 67 million years ago,” Dr. McKellar said in the release.

“Our analyses of body shapes in the fossils suggests that the turnover was not related to major differences in ecology, but it may have been related to something like the size and complexity of ant colonies. More work is needed to confirm this.”

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Meteors, UFOs or something else? Dawson City, Yukon, residents puzzled by recent sightings in night sky – CBC.ca

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Some residents in Dawson City, Yukon, say they’ve been seeing unusual things in the night sky lately — and it’s not the Northern Lights. 

But some might say it’s equally as fascinating.

Over the past few weeks, some residents have taken to social media to report seeing what they described as a fireball or meteor overhead. And last week, two residents said they both saw something similar.

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Naomi Gladish lives in Henderson Corner, a subdivision approximately 20 kilometres from downtown Dawson City. She told CBC News she saw something while walking her dog Friday morning.

“I looked up and saw a bright star,” Gladish said. “Or what I thought was a star.” 

“Within a fraction of a second, I realized it was actually moving quickly. And then as I watched it, a second later it grew a long tail.”

Dawson City resident Naomi Gladish said she saw something similar to the fireball shown in this image from the American Meteor Society. (American Meteor Society)

Gladish said the unknown object started to change into a pale blue colour, like a gas flame. Then, a few seconds later, it appeared to burn out.

“I could see fire, or coal,” Gladish said. “Like red glowing bits, breaking off of it. And then that was it. I tried watching to see if I could see any dark chunks falling from that spot, or carrying on from that spot, but the sky was dark.”

A minute or two after Gladish saw what she thought was a meteor, she heard a boom in the distance.

“My dog and I both turned our head to that exact direction that I had just seen it,” she said.”I figured it was related.”

Two women walking through snowy mountain terrain.
Naomi Gladish hiking with her sister at Tombstone Park. (Submitted by Naomi Gladish)

Dawson resident Jeff Delisle reported seeing something similar at about the same time. He then took to social media to ask if anyone else had seen it. Two people responded saying they had. 

“It flew right above me,” Delisle wrote.

“Pretty cool looking…. What is it?”

Likely not a meteor, says astronomer

Christa Van Laerhoven, president of the Yukon Astronomical Society, came across Delisle’s post and got in touch. She asked about what he’d seen, such as how long it was in the sky and the colour.

Van Laerhoven told CBC News that based on descriptions from both Delisle and Gladish, she doesn’t believe it could have been a meteor.

She says a meteor would have been moving much faster, and the colouring would have appeared differently. 

“Meteors can be any colour but … as a rule, are a consistent colour. What these people were describing had different colours. So the head looked blue and then the tail was more of an orange,” van Laerhoven said.

“That’s just something that doesn’t happen with meteors.”

a meteor
This zoomed-in still from a dashcam video captured in 2020 by Louise Cooke from Mount Lorne, Yukon, shows what one space science expert said appears to be an unusually-bright meteor travelling across the sky. (Submitted by: Louise Cooke)

Van Laehoven believes there may be another explanation for the recent unusual sightings: space junk, falling to earth.

“Space junk, when it comes in … comes through the atmosphere and starts glowing that can be more irregular, because of the variety of materials that go into a spacecraft.”

Van Laerhoven also suggested it could a very fast plane, or someone playing with rockets.

Gladish, however, doesn’t think anyone in Dawson was playing with rockets on Friday morning.

“Unless they’re talking about someone in China, or like a distant land playing with very high, powerful rockets … then sure,” she said.

“This was not something that someone in Dawson was doing … This came from much, much higher and it was much, much different to anything that would be locally caused.”

Van Laerhoven also dismissed another possibility: alien visitors.

“If aliens were coming to Earth, we would know,” she said.

“Simply because it would take them so much effort to get here that it would be very hard to imagine them getting here and not doing something dramatic enough that we would actually know about it.”

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