Frozen Microbes From The Distant Past Threaten To Wake Up, Ready To Infect People, Plants, And Animals
uried beneath the world's permafrost lies a mob of microbial villains that predate human civilization. Viruses, bacteria, and other ancient microbes have been suspended there for tens of thousands of years, quietly dormant. Now, as rising temperatures gnaw away at the planet's ice, they are beginning to stir. The most obvious nightmare scenario is a pandemic, but here's a threat you probably didn't see coming: your potatoes.
The 48,500-year-old virus awakens
In 2022, scientists from Aix-Marseille University in France
revived 13 viruses from samples of permafrost collected in the icy Russian far east, including one that dated back 48,500 years – the oldest virus ever reawakened.
They also revived three new viruses from a 27,000-year-old sample of frozen mammoth poop and a chunk of permafrost stuffed with a large amount of mammoth wool, aptly named
Pithovirus mammoth, Pandoravirus mammoth, and
Megavirus mammoth. A further two new viruses were isolated from the frozen stomach contents of a Siberian wolf, named
Pacmanvirus lupus and
Pandoravirus lupus.
Most shockingly, the pathogens had not lost their bite after lying idle for tens of thousands of years. With some coaxing, the viruses were still viable and able to infect a single-celled amoeba.
While this was all carried out in a lab, the researchers explained that the risky research highlighted grave risks to the real world.
“It is thus likely that ancient permafrost [...] will release these unknown viruses upon thawing,” the researchers wote in their paper, published in 2023 in the journal
Viruses.
“How long these viruses could remain infectious once exposed to outdoor conditions, and how likely they will be to encounter and infect a suitable host in the interval, is yet impossible to estimate, but the risk is bound to increase in the context of global warming, in which permafrost thawing will keep accelerating, and more people will populate the Arctic in the wake of industrial ventures,” they concluded.
Permafrost pathogens have already taken lives
If pathogenic microbes like this were to infect humans en masse, the impacts could be devastating. The world had a small taste of this in 2016 when
dozens of people fell sick in the Yamal Peninsula of Siberia. It turned out that a heatwave had melted permafrost in the area, exposing a reindeer carcass that had been infected with anthrax decades ago. Somehow, the bacteria spread, killing one child and leading to the culling of more than 200,000 reindeer.
Some scientists
tried to quell those fears by suggesting the Yamal outbreak was linked to population growth in the area and a drop in deer vaccination. Nevertheless, it reignited the debate about whether long-lost microbes could return to infect humans once again.
The threat to food
But human disease isn’t the only threat. A much less pondered scenario is that thawing permafrost could expose pathogens that target crops, triggering serious disruptions to agriculture and the global food system.
In a recent
study, scientists from the Korea Polar Research Institute brought permafrost samples from Alaska's Seward Peninsula back to the lab and let them thaw. Over 90 days, one microbe staged a quiet coup. Pseudomonas, a pathogenic bacterium responsible for potato soft rot, a disease that turns many different crops into a mushy slurry, rapidly grew in number, surging to dramatic new levels as the ice released its grip. The bacteria from the thawed permafrost were then placed onto potato tubers, which they infected and transformed into an inedible sludge.
