Context: European researchers have raised concerns of yet another pandemic after resurrecting a 48,500-year-old ‘zombie virus’ from a frozen lake in Russia.

• Climate change-induced thawing of the permanent frozen land (permafrost) in the Arctic could pose a new public health threat.

About Zombie Virus

• Zombie virus is the term given to a virus that is frozen in ice and therefore dormant. Zombie viruses have been dormant for many years due to being trapped inside the ice and have come to life after the ice melted.

Key Findings

• European researchers have recently found 13 “zombie viruses” from Russia’s Siberian permafrost. 

• One among these 13 zombie viruses has been named as Pandoravirus yedoma after the mythological character Pandora. This virus was 48,500 years old, a record age for a frozen virus returning to a state where it has the potential to infect other organisms. 

• This has broken the previous record held by a 30,000-year-old virus discovered by the same team in Siberia in 2013.

What is the cause of the revival of zombie viruses?

• One-quarter of the Northern hemisphere is underlain by permanently frozen ground, referred to as permafrost.

• Due to climate warming, irreversibly thawing permafrost is releasing organic matter frozen for up to a million years, most of which decomposes into carbon dioxide and methane, further enhancing the greenhouse effect.

• Part of this organic matter also consists of revived cellular microbes (prokaryotes, unicellular eukaryotes) as well as viruses that remained dormant since prehistoric times.

What will be the impact of these zombie viruses?

• All of the “zombie viruses” have the potential to be infectious and hence pose a “health danger” after researching the live cultures.

• It is believed that pandemics like Covid-19 will become more common in the future as melting permafrost releases long-dormant viruses.