While scientists are trying to determine the starting point of the coronavirus pandemic, one group of virologists is trying to find out where and how the once devastating disease – the flower – emerged.
Recently, in northern Europe, in the archeological remains of the Viking Age, they found the viral DNA of an ancient strain.
Samples of A.D. y. It dates back to 603 BCE and provides crucial genetic evidence that the flower existed more than 1,000 years before the best records available to us.
The flower is caused by the variola virus (VARV) and is by this time the first and only disease that has completely defeated humanity in humans through vaccination; This victory was finally signed in 1980. In the twentieth century, the flower has killed between 300 and 500 million people.
The probable historical distribution of the flower can be determined. Scholars suggest that it was first introduced to Europe by the Moors during the invasions of Spain and Portugal in the 8th century, and later spread to Europe during the Crusades.
A flower-like rash has also been reported on the mummy of Pharaoh Ramses V of Egypt, who died in the 6th century BC. y. Died in 1157; This suggests that the flower may have spread as far back as 3,000 years ago.
However, this is only speculation and is not based on viral DNA studies. It is difficult to find such evidence.
Scientists do not yet know exactly, but suspect that the flower virus appeared in rodents in Africa several thousand years ago and then spread to humans. Appropriate samples are required to prove this.
To find out how the ancient flower viruses and modern strains are related, researchers will also be helped to study the origin and development of the flower. Such research is possible only with samples of ancient viral DNA.
Prior to the above-mentioned recent discovery, the oldest sample of DNA in our possession belonged to a 17th-century mummy found in Lithuania; Specimens belonging to 19th and 20th century mummies preserved in the Czech National Museum were also available. Comparing the DNA of these specimens with the modern flower virus, it was determined that their most recent common ancestral virus must have been in the years 1530-1654.
Barbara Muhlehmann, a virologist at the Center for Pathogenic Evolution at the University of Cambridge, and her colleagues looked for traces of an ancient flower in 1870 individuals who have lived on the Eurasian and American continents since 31,000 years ago.
“Ancient viral sequences recovered from archaeological remains provide direct molecular evidence of past infections, and at the same time, discrepancies between possible written sources of historical infections and available ancient genetic sequences can be resolved,” the group said in a statement.
The crucial finding turned out to be fragments of ancient viral DNA fragments related to the modern flower from the bones and teeth of 26 individuals who died long ago in northern Europe. 11 of them belong to the Viking Age and A.D. წ. It dates back to 603-1500.
Out of these 11 human samples, the group was able to recover an almost complete viral genome from the remains of only four people, but even that was enough to get the evidence they were looking for.
“Viking-era sequences trace the earliest date of VARV infection in humans to about 1,000 years ago and reveal the existence of hitherto unknown, extinct viral offshoots,” the researchers wrote.
According to them, A.D. y. The 603 aVARV specimens coincide with numerous written documents that presumably describe the spread of flower infection in southern and western Europe from the late 6th century.
Such results also support the current theory that the flower first appeared in rodents – the ancient viral specimens, more closely related to the modern flower virus, were indeed more closely related to Taterapox, another virus in the proxivirus family that infects rodents.
According to virologist Antonio Alcami, the now extinct aVARV had several additional genes that modern flowers do not have. These genes are also found in other less dangerous poxiviruses and may have helped aVARV in its time to infect various host animals.
“The ancient VARV virus may have evolved into a relatively common zoonosis that has caused mild infections in humans, rodents and other hosts for centuries,” Alkami said.
Ancient viruses hitherto unknown were discovered in the ice 15,000 years ago
Similar: Ancient viruses hitherto unknown were discovered in ice 15,000 years ago
Researchers are not sure yet. The now extinct ancient virus was widespread in northern Europe, but DNA alone cannot tell us much about its severity. According to them, it is impossible to prove that these individuals died as a result of the infection.
By observing the various characteristics of gene inactivation in the ancient viruses discovered during the study, solving them at this stage can only say that this virus circulated widely among humans even during the Viking Age, for at least 450 years.
The study was published in the journal Science.