More than 1,700 previously unknown viruses discovered in melting ice

Scientists have discovered more than 1,700 ancient viruses lurking deep inside a glacier in western China, most of which have never been seen before. 

It raises concerns that, as the world warms and ice melts, it could unleash pathogens unknown to science and spark a deadly pandemic. 

Researchers found the viruses in an 1,000-foot-long ice core extracted from the Guliya Glacier on the Tibetan Plateau, located at the intersection of Central, South and East Asia. 

The viruses date back as far as 41,000 years and have survived three major shifts from cold to warm climates. 

Just one day after the researchers published their study, rapper-turned-actor Chris 'Ludacris' Bridges posted a video of himself drinking meltwater from an Alaskan glacier.

The video got millions of views on TikTok and Instagram, sparking a wave of concern that he was risking his life by drinking untreated glacier water. 

But a glaciologist has since stated that 'he's totally fine,' and that water from a glacial melt stream is 'about the cleanest water you'll ever get.'

The public's concerns aren't totally unfounded, however. 

Deadly pathogens have emerged from melting permafrost at other locations around the world, stoking fears over a potential outbreak.

In 2016, for example, anthrax spores escaped from an animal carcass that had been frozen in Siberian permafrost for 75 years. Dozens were hospitalized and one child died.

But luckily, all 1,700 viruses found in this latest study pose no threat to human health, the researchers stated. 

That's because these viruses can only infect archaea - which are single-celled organisms - and bacteria. They cannot make humans, animals or even plants sick.

But studying them is important because they offer a window into Earth's deep climactic history, and could help us understand what future microbial communities could look like. 

The team of researchers led by The Ohio State University drilled over 1,000 feet into the Guliya Glacier, a massive icecap located in the northwestern Tibetan Plateau. 

The resulting ice core was separated into nine segments, each one representing a different time horizon and climactic period. The segments ranged from 160 to 41,000 years old. 

The researchers extracted DNA from each segment and used a process called metagenomic analysis to identify each individual viral strain. 

They ended up cataloguing about 50 times more viral information than scientists have ever collected from glaciers before. 

From their analysis, the researchers found that the viral communities looked very different depending on the climactic conditions at the time they were frozen.

'We saw clear shifts in the viruses that existed under colder climates versus warmer climates,' study co-author and The Ohio State University microbiologist Matthew Sullivan told Popular Science.

For example, a distinct community of viruses took shape 11,500 years ago, while the climate was shifting from the cold Last Glacial Stage to the warmer Holocene Epoch, which we are currently in.  

'This at least indicates the potential connection between viruses and climate change,' said study co-author ZhiPing Zhong, a microbiology research associate at The Ohio State University. 

Sullivan, Zhong and their colleagues published their findings in the journal Nature Geosciences.