Are humans 'freezing' their diseases on Mount Everest? Yes, finds study

Every year, approximately 800 people attempt to climb Mount Everest during the few weeks of the year when the weather conditions are suitable and just proper.

While it’s an enthralling and challenging climb, the world’s highest terrace is laden with human trash, discarded oxygen cylinders, tents, human feces, and even dead bodies. Yes, you read that right. In fact, some of those dead bodies even serve as a mile-marker for the climbers.

But that’s not all humans are leaving behind on the world’s highest peak.

A recent study on microorganisms found at high elevations revealed a low diversity of bacteria, protists, and fungi left by the climbers scaling Mount Everest, which is now acting as a deep freezer for these organisms. These microorganisms can lay dormant for decades and even centuries.

Microbes on Mount Everest

Even though the environmental conditions are extreme up there at 7,900 feet above sea level, researchers have been able to collect and cultivate the fungi and bacteria. It’s believed that most of these microorganisms aren’t alive, given the weather experienced at such high elevations.

However, what surprised the scientists was that these microorganisms - Staphylococcus, one of the most common skin and nose bacteria, and Streptococcus, the dominant genus in the human mouth - could survive and lay dormant in the extreme cold.

Senior author Steven Schmidt, a microbial ecologist at the University of Colorado Boulder, said in a press release, "If somebody even blew their nose or coughed, that's the kind of thing that might show up."

Scientists have always known that there were microbes present on Everest. Still, the samples collected by the team represent the highest elevation sediment environment to be explored for microorganisms using cultivation-independent next-generation sequencing methods.

The researchers collected samples from the South Col of Mount Everest, a camping base for hundreds of climbers preparing to scale the mountain till the end, as part of the National Geographic and Rolex Perpetual Planet Everest Expedition from April to May 2019.

The researchers believe this study has implications for the potential for life far beyond Earth.

“We might find life on other planets and cold moons,” said Schmidt. “We’ll have to be careful to make sure we’re not contaminating them with our own.” 

The full study was published in Arctic, Antarctic and Alpine Research and can be found here.

Study Abstract:

Microbial communities in alpine environments >7,500 m.a.s.l. have not been well studied using modern cultivation-independent sequencing approaches due to the challenges and danger associated with reaching such high elevations. For this reason, we know little about the microorganisms found in sediments on Earth’s tallest mountains, how they reach these surfaces, and how they survive and remain active at such extreme elevations. Here, we explore the microbial diversity recovered from three sediment samples collected from the South Col (~7,900 m.a.s.l.) of Sagarmatha (Mount Everest) using both culturing and next generation sequencing approaches (16S rRNA gene, internal transcribed spacer [ITS] region, and 18S rRNA gene sequencing). Both approaches detected very low diversity of bacteria, protists, and fungi that included a combination of cosmopolitan taxa and specialized microorganisms often found at high elevations like those of the genera Modestobacter and Naganishia. Though we managed to grow viable cultures of many of these taxa, it remains likely that few, if any, can be active in situ at the South Col. Instead, these high-elevation surfaces may act as deep-freeze collection zones of organisms deposited from the atmosphere or left by climbers scaling the Earth’s highest mountain.