Humanity is facing a bizarre new pandemic threat, scientists have warned. Ancient viruses frozen in the Arctic permafrost could one day be released by Earth’s warming climate and trigger a major disease outbreak, they say.
Strains of these Methuselah microbes – or zombie viruses as they are also known – have already been isolated by researchers who have raised fears that a new global medical emergency could be triggered – not by a disease new to science, but by a disease from the distant past.
As a result, scientists began planning an Arctic monitoring network that would identify early cases of a disease caused by ancient microorganisms. In addition, it will provide quarantine and expert medical treatment to infected people in an effort to contain an outbreak and prevent infected people from leaving the region.
“At the moment, analyzes of pandemic threats focus on diseases that can emerge in southern regions and then spread north,” said geneticist Jean-Michel Claverie of Aix-Marseille University. “In contrast, little attention has been paid to an outbreak that could emerge in the far north and then travel south – and that’s an oversight, I believe. There are viruses up there that have the potential to infect people and a new disease -starting an outbreak.”
This point was supported by virologist Marion Koopmans of the Erasmus Medical Center in Rotterdam. “We don’t know what viruses are out there in the permafrost, but I think there is a real risk that there could be one that could cause a disease outbreak – say, of an ancient form of polio. We have to accept that something like this can happen.”
In 2014, Claverie led a team of scientists who isolated live viruses in Siberia and showed that they could still infect single-celled organisms – even though they had been buried in permafrost for thousands of years. Further research, published last year, revealed the existence of several different viral strains from seven different locations in Siberia and showed that they can infect cultured cells. One virus sample was 48,500 years old.
“The viruses we isolated could only infect amoebae and posed no risk to humans,” Claverie said. “However, this does not mean that other viruses – which are currently frozen in the permafrost – may not cause disease in humans. We have identified genomic traces of smallpox viruses and herpes viruses, which are known human pathogens, for example.”
Permafrost covers a fifth of the northern hemisphere and consists of soil that has been kept at sub-zero temperatures for long periods of time. Some layers have remained frozen for hundreds of thousands of years, scientists have discovered.
“The crucial point of permafrost is that it is cold, dark and lacking in oxygen, which is perfect for preserving biological material,” Claverie told the Observer last week. “You can put a yogurt in permafrost and it can still be edible 50,000 years later.”
But the world’s permafrost is changing. The upper layers of the planet’s main reserves – in Canada, Siberia and Alaska – are melting as climate change affects the Arctic out of proportion. According to meteorologists, the region is warming several times faster than the average increase in global warming.
However, it is not directly melting permafrost that poses the most immediate risk, Claverie added. “The danger comes from another global warming impact: the disappearance of Arctic sea ice. This is allowing increases in shipping, traffic and industrial development in Siberia. Huge mining operations are being planned, and are going to blow huge holes into the deep permafrost to extract oil and to mine ore.
“Those operations will release large amounts of pathogens that still thrive there. Miners will walk in and inhale the viruses. The consequences can be disastrous.”
This point was emphasized by Koopmans. “If you look at the history of epidemic outbreaks, one of the key drivers is land use change. Nipah virus is spread by fruit bats which have been driven out of their habitats by humans. Similarly, smallpox is linked to the spread of urbanization in Africa. And that’s what we’re going to see in the Arctic: a complete change in land use, and that can be dangerous, as we’ve seen elsewhere.
Scientists believe that permafrost – at its deepest levels – may contain viruses that are up to a million years old and therefore much older than our own species, which is thought to have originated around 300,000 years ago.
“Our immune systems may never have been in contact with some of those microbes, and that’s another concern,” Claverie said. “The scenario of an unknown virus once infecting a Neanderthal coming back to us, although unlikely, has become a real possibility.”
For that reason, Claverie and others are working with UArctic, the University of the Arctic — an international educational network in the polar region — on plans to establish quarantine facilities and provide medical expertise that can identify early cases and treat them locally to try to contain . the infection.
“We are now facing a tangible threat and we must be prepared to deal with it. It’s as simple as that.”