In the bones and teeth of people who lived in 600-1050 years BC in Northern Europe and on the territory of modern and the UK, found DNA from a previously unknown strains of variola virus, was reported in Science. Compared with more modern strains showed that the last common ancestor of varieties of variola virus existed about 1700 years ago, and by the VI century ad, the disease is widely distributed in Europe, and mortality from it then, most likely, was lower than during later outbreaks. It turns out that the variola virus, unlike many other non-cellular parasites, over time, has become more dangerous for his master.
Cases of smallpox has not been since 1978, and before that she had claimed millions of lives: only in XX century — from 300 to 500 million. Where there was a smallpox and when this happened is not known. Mention of smallpox, probably found in the old Testament, and the lesions on the skin of the mummy of Ramses V (who died in 1157 BC) resemble pockmarks. However, in 2018 the study of the DNA of the virus is the causative agent of this disease discovered in the remains of a boy who lived in Lithuania in the seventeenth century of our era, says that the majority of strains appeared recently, between 1588 and 1645 years. A new study of the DNA of the causative agent variola virus ( Variola) from the remains of people of different ages should help to understand, and when actually having the disease.
One such study conducted by scientists from Armenia, great Britain, Denmark,, Sweden and other European countries. Director gave Willerslev Eske (Eske Willerslev) from the University of Cambridge. Scientists searched for the DNA fragments of the virus Variola in 1867 the remains of people who lived in Eurasia or the Americas 31630-150 years ago. The genes of the ancient variants of the smallpox virus were compared with those that were characteristic of the young of his species. Age human remains and the average rate of appearance of mutations in DNA viruses, the researchers identified which properties had to re-open the options of the causative agent of smallpox, and when there was a last common ancestor known strains of Variola.
Not every one of those whose remains were tested for the presence of viral DNA, suffered from smallpox. Fragments of genetic material Variola found only 13 of them, though only the Europeans. Of these, 11 patients lived in the Viking age in 600-1050 years BC, i.e. the oldest of them — for a thousand years before the first confirmed case of smallpox. DNA viruses in them was badly damaged, so any fully reconstruct the genomes of Variola was possible only in four cases.