A 46,000-year-old worm has been revived from the Russian permafrost—could deadly germs be next?

In 2020, I wrote a series of blog posts about whether ancient microbes could survive millennia in the ice. As it turns out, some can. 

This week, Russian scientists announced that they had resurrected roundworms that had laid beneath Siberia since the last Ice Age. The frozen worms, which were smaller than pencil tips, were found in a fossilized gopher burrow buried 130 feet deep within the permafrost. Permafrost is soil that has been frozen for a long time, in some cases thousands of years. Because it is so cold, it is great for preserving the remains of plants and animals. 

The researchers took the soil samples to the lab, where they identified the creature as a type of roundworm. Roundworms are simple, tube-shaped creatures that are found all over the world. Many roundworms are good for the soil, but some can cause diseases. 

When researchers put the worms in water, something miraculous happened: the worms woke up. They flourished in the lab’s carefully-monitored conditions, giving birth to over a hundred generations of new worms. 

These worms, now named Panagrolaimus kolymaenis, have the rare ability to enter a near-death state called cryptobiosis. During this time, the worms—and all of their life functions like eating and growing—slow down to a near standstill. The ability allows them to survive unthinkable conditions like extreme cold, extreme heat, or lack of oxygen. 

Other creatures can also enter cryptobiosis. For example, some bacteria, including anthrax, form spores—tiny, hibernating cells that can survive for untold amounts of time in extreme conditions. However, it’s rare to find examples who have survived since ancient times.

That doesn’t mean it hasn’t happened. Other researchers claim to have revived 30,000-year-old and 48,500-year-old viruses from Russian permafrost, a 42,000-year-old bacterium from the Alaskan tundra, and an 8-million-year-old bacterial spore from Antarctic ice. Most of these germs don’t infect humans, but more simple creatures like amoebas. 

But human infections aren’t impossible. In one frightening case, anthrax spores in melting Russian permafrost sickened reindeer and villagers and killed a 12-year-old boy. 

As the climate warms, that permafrost is melting at unprecedented rates. It currently covers large areas of the Arctic and surrounding areas, often far beyond the watchful eyes of public health officials. Some scientists, like Dr. Teymuras Kurzchalia, who helped run the worm study, fear that some germs might be able to survive in the wild and cause outbreaks.

Luckily, scientists say that the risk for outbreaks caused by germs in melting ice remains low. The environment is filled with microbes, and most are harmless or even helpful. In fact, very few infect humans at all. Meanwhile, it is still rare for germs to survive in the ice, let alone the thawing process. But just in case, some researchers, like Birgitta Evengård of Umea University, want better resources and disease surveillance systems in the far North.

Most scientists are more worried about the more pressing effects of climate change, like extreme heat and flooding. In the far North, melting permafrost also can release toxins and radioactive waste from the Cold War.

In the end, the researchers all agree on one thing: climate change is going to have big impacts on human health. 

Original Blog Posts:

Pathogens in the Permafrost: Could Melting Ice Unleash Ancient Diseases? Part 1

Pathogens in the Permafrost: Could Melting Ice Unleash Ancient Diseases? Part 2


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