As scientists worldwide are trying to find the origin of the coronavirus, other virologists continue to struggle to trace the origins of another disease that once devastated the world, namely smallpox. The good news is, traces of the smallpox disease are finally beginning to appear. Researchers have successfully discovered the viral DNA of an extinct ancient smallpox strain found in Viking-era archaeological remains in northern Europe. The earliest DNA samples date back to 603 BCE. This finding provides genetic evidence that the origin of smallpox emerged at least 1,400 years earlier than previously recorded.
As quoted from Medicalxpress, Friday (24/7/2020), an international research team has sequenced the genome of virus strains found in Viking teeth across Viking-era burial sites in Northern Europe. "We discovered new smallpox strains in Viking teeth and the genetic structure of the smallpox is different from the modern smallpox virus eradicated in the 20th century. We know Vikings traveled to Europe and its surroundings and they suffered from smallpox. Thus, it is also possible that Vikings spread smallpox," stated Eske Willerslev, the lead researcher of this study. Furthermore, researchers stated that the 1,400-year-old genetic information is highly important because it teaches us about the evolutionary history of the variola virus that causes smallpox.
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