The threat of viruses lurking in ancient ice blocks.

A team of researchers in the United States has made a remarkable discovery while studying ancient viruses inside the ancient ice sheet known as Guliya on the Tibetan Plateau in China.

In 2015, the research team drilled 50 meters deep into this 15,000-year-old ice block and collected two ice cores to study what bacteria were present in the atmosphere at the time they became trapped inside the ice.

Two ice cores were drilled at different altitudes: 6,200 m and 6,650 m. Researchers found that environmental conditions at these two locations differed significantly in terms of air temperature, atmospheric oxygen concentration, and ultraviolet radiation. Analysis of these two ice cores can help scientists understand the environmental and climatic conditions at the time, as well as provide scientific predictions as ice melt is rapidly occurring across the globe.

Newly published analysis results show that these ice cores contain up to 33 different groups of viruses. Remarkably, according to the researchers, 28 of these groups are completely new to modern science. Furthermore, some of these viruses can grow and reproduce at temperatures as low as -20°C.^oC to 10^oC.

Very little is known about how bacteria and viruses become trapped in ice for thousands of years. Only two studies on viruses found in glaciers exist – one sampled from a 140,000-year-old Greenland ice core and another sampled from ice cores at depths of 2,749 to 3,556 meters at the Vostok Station in East Antarctica.

The research team warns that the continued rapid melting of glaciers and ice sheets around the world, driven by global warming, could lead to a worst-case scenario: the release of viruses and bacteria that have been trapped inside ice for hundreds of thousands of years, potentially causing unpredictable consequences.

Therefore, scientists are racing against time and climate change to collect and identify bacteria and viruses found within ancient ice sheets. Doing so could help modern science better understand pathogens that once plagued the past, thereby providing more support for research efforts on pathogens that may emerge in the future.

This information was released amidst a global outbreak of acute pneumonia caused by the novel coronavirus.

My Tong