●Fresh Research into the origins of the Smallpox disease
•Smallpox is a contagious disease, caused by the Variola Virus (VARV).
•The origins of smallpox have always been unclear
•New research suggest that the smallpox was in existence as early as during the ‘Viking age’ in the 8th century CE.
[Viking Age was the period during the Middle Ages when the Norsemen (name given to the Scandinavian Vikings) undertook colonizing, conquest and trading throughout Europe, and reached North America in the 9th and 10th century.]
•Until now, the earliest confirmed case of the disease was found in the mummified remains of a 17th century Lithuanian child, even though written records suggest that it is much older
•The Variola virus sequence was recovered from 13 Northern European individuals including 11 dated to 600–1050 CE, overlapping the Viking Age.
•Pan European Presence: These sequences, combined with early written records of VARV epidemics in southern and western Europe, suggest a pan-European presence of smallpox from the late 6th century.
•According to the study, the virus was circulating among people even earlier, about 1700 years back at the time when the Western Roman empire declined and people were migrating across Eurasia.
• It also suggests that the genetic makeup of the viral strain recovered from the 11 individuals is different from the modern version which was eradicated in 1979-80.
•The Viking variant of the virus is part of a previously unknown, and now extinct virus group, or clade.
•Both the modern smallpox and the ancient variant descended from a common ancestor but diverged 1700 years ago.
•Course of Evolution: It was suggested as a benign disease (less dangerous) considering that smallpox may have in the past been a mild.
•In the course of evolution, the active gene count of the virus is shown to have reduced due to mutation.
•Therefore, the researchers speculated that smallpox became more deadly over time.
•Implications of the New Research:
Information about the Viruses: The results of the study does not have any impact on the current spread of the Covid-19 pandemic. However, it does provide important information on how a virus may become deadlier over time.
•Trace of History: Nonetheless, it is important to note that smallpox is the latest among several other diseases whose history in recent years have been rewritten by ancient DNA analysis.
•Earlier, In 2015, a study noted that the plague that killed millions in medieval Europe can be traced as far back as the Bronze age between 3000 and 1000 BCE.
•In 2018, on the other hand, Hepatitis B was seen to have origins in the Bronze age as well.