Evidence has emerged that the common cold virus has been around for longer than previously believed. A lot longer, in fact. In a study published online in the open access journal bioRxiv, a team of microbiologists and genetic researchers from Copenhagen University explain how they recovered residues of the adenovirus C in a pair of 31,000-year-old teeth. The teeth that produced these viral samples were recovered from an archaeological site on the tundra of northeastern Siberia, near the Yana River. They belonged to a child who was part of an ethnic group known as the Ancient North Siberians, who were ancestors of modern Native Americans.
Human pathogenic viruses causing respiratory and enteric infections include the Adenovirus C, which is known to cause the common cold. Adenovirus C was found in Siberia, based on the latest research report, which is the oldest evidence ever of the common cold in humans: 31,000 years ago! ( Kateryna_Kon / Adobe Stock)
The Oldest Ever Virus Found In Humans: The Common Cold!
Adenovirus C is one of several viruses that are known to cause the common cold. Its presence in an ancient human fossil, a child’s tooth in this case, is unprecedented!
The ancient sample was “the oldest virus [found] in humans yet,” according to Danish microbiologist and lead study author Sofie Holtsmark Nielsen, who spoke with the New Scientist about her team’s remarkable achievements. It represents “the first molecular evidence that early modern humans in the Pleistocene hosted common childhood viral infections,” Nielsen and her partners wrote in their bioRxiv article.
Previously, the oldest viral sample taken from a human specimen was just 7,000 years old.
In the same study, the scientists also found four versions of the modern herpes virus , including herpes simplex-1, which can cause cold sores to develop. Viruses of many types were obviously well-established in human populations tens of thousands of years ago, during the Pleistocene epoch when glaciers still covered a sizable area of the Earth.
When humans have the common cold or the flu, leukocytes (white; white blood cells) attack the virus (green). In this 3D illustration there are red blood cells and white blood cells; the common cold or flu virus is green. ( Siarhei / Adobe Stock)
Tracing the Evolution of the Common Cold
As amazing as their initial discovery was, the Danish researchers weren’t finished.
Taking their research one step further, they compared their 31,000-year-old adenovirus C residues with samples of the modern version of the virus. The idea was that by comparing and contrasting these two closely related but still different entities, they could determine how long ago they diverged from a common evolutionary ancestor.
The scientists employed the most advanced analytical tools available in evolutionary science and microbiology in their search for an answer. Eventually, they determined that the two adenovirus C samples could be traced back to a common ancestor that existed sometime between 487,000 and 963,000 years ago, with an estimated date of 702,000 years ago being the most likely time that such a virus would have been found in nature.
If this estimate is correct, it means the common cold has been around for at least 400,000 years longer than the modern version of Homo sapiens (us). The common cold virus would have relied on archaic human species like the Neanderthals and the Denisovans to act as its hosts. It would have entered the Homo sapiens line through interactions with such archaic hominin species, like the one that occurred when modern humans met Neanderthals after migrating out of Africa approximately 60,000 years ago.
In fact, the genetic analysis performed in this new study found signs of a change in the makeup of the virus that had occurred sometime within the last 70,000 years. This could mean that the cold virus jumped from Neanderthals to modern humans once they started living together and interbreeding.
Different groups have mixed and migrated throughout Siberia in Russia and into North America over the past 40,000 years. Based on the latest research study, it was the Ancient North Siberians (Eurasians) that first caught the “thing” we know as the common cold. (Martin Sikora / Nature)
The Ancient North Siberians and The First Native Americans
The Yana Rhinoceros Horn Site in northeastern Siberia was first excavated 20 years ago. It has produced prodigious quantities of animal bones, along with stone tools and other evidence showing humans had settled in the area in ancient times.
Only after examining the 31,000-year-old children’s baby teeth, which were unearthed in 2019, did scientists realize they’d found the remains of a previously unknown ethnic group of modern humans. These people were dubbed the Ancient North Siberians , and scientists say they are the closest ancestors of Native Americans that have ever been found.
The two 31,000-year-old milk teeth found at the Yana Rhinoceros Horn Site in Russia which led to the discovery of a new group of ancient Siberians: the Ancient North Siberians (Eurasians). (Russian Academy of Sciences / Nature)
Living in some the of coldest areas on the planet near the end of the last Ice Age, the Ancient North Siberians survived by hunting woolly mammoths, woolly rhinoceroses, and bison. About 24,000 years ago, the Ancient North Siberians split into two genetically distinct groups, one that would stay in the area from then on and another that would eventually be on the move.
A few thousand years later, sea levels plunged and the Bering Strait land bridge opened between ancient Siberia and the unexplored North American continent. At that time, one group of Ancient North Siberian descendants took the opportunity to cross the bridge before migrating southward and eastward. These would have been the direct ancestors of at least some modern-era Native Americans, and also the descendants of the original Ancient North Siberians.
Scientists say the Ancient North Siberians were well-suited for long-distance exploration and settlement.
“They adapted to extreme environments very quickly, and were highly mobile,” explained Martin Sikora, a genetic researcher affiliated with the Copenhagen University’s Lundbeck Foundation Centre for GeoGenetics. Sikora was involved in the 2019 study (published in Nature) that revealed the existence of the Ancient North Siberians and was a participant in the new ancient viral study as well.
“These findings have changed a lot of what we thought we knew about the population history of northeastern Siberia, but also what we know about the history of human migration as a whole,” Sikora told the Daily Mail back in 2019.
Many new viruses were introduced to North, South, and Central America by European explorers in the 15 th and 16 thcenturies. Many of these viruses were highly lethal to Native Americans, who lacked immunity to these disease carrying microbes.
But it seems the common cold virus had already been around for more than 10,000 years by the time the Europeans arrived in the New World, having been carried across the Bering Strait land bridge by the Ancient North Siberians who then became the first North Americans!
Top image: A scientific illustration of what the Upward Sun River camp in the Tanana River Valley, Alaska, where the oldest Beringia remains (of a child) were found. Source: Eric Carlson in collaboration with Ben Potter
By Nathan Falde