Researchers have taken the opportunity to measure the number of viruses circling around in the atmosphere, and the number of viruses that are falling back down to the surface of the Earth is no less than billions of viruses. This high number of viruses can likely explain why extremely similar viruses are spreading across the different parts of the world.
Researchers probed the atmosphere from sites in the Sierra Nevada Mountains in the south of Spain. According to the scientists, billions of viruses are being swept up beyond 9,000 feet.
“Every day, more than 800 million viruses are deposited per square meter (11 square feet) above the planetary boundary layer,” explained University of British Columbia virologist Curtis Suttle, a senior author of the study, in a statement.
The boundary layer of the planet is located in the lowest part of the troposphere and it’s responding to the conditions that are present on the surface of the planet. Scientists decided to measure the number of viruses located in the upper troposphere for the first time. The upper troposphere is located above the weather systems of the planet, although it sits beneath the beginning of the stratosphere.
The viruses are traveling upwards on ocean spray and soil-dust. That way they can travel for thousands of miles through the upper troposphere before falling back to Earth. Thanks to this study, researchers have a better understanding of how genetically similar viruses are spreading across the globe.
“Roughly 20 years ago we began finding genetically similar viruses occurring in very different environments around the globe…. It’s quite conceivable to have a virus swept up into the atmosphere on one continent and deposited on another,” Suttle explained.
The researchers located far less bacteria traveling above the planetary boundary layer. There are only tens of millions falling per square meter. The reason why there are billions of viruses is because they have more atmospheric sticking power compared to bacteria, as bacteria can easily be carried away by rain.
“Bacteria and viruses are typically deposited back to Earth via rain events and Saharan dust intrusions. However, the rain was less efficient removing viruses from the atmosphere,” author and microbial ecologist Isabel Reche from the University of Granada in Spain was quoted in the statement.
Even though billions of viruses are falling through the skies, we shouldn’t be too worried. According to the scientists, the microbe transportation mechanism could be good for ecosystems and help them prosper.
“Rather than being a negative consequence, this deposition provides a seed bank that should allow ecosystems to rapidly adapt to environmental changes.”
Also, according to a report in Newsweek, a high number of those viruses are likely not active.
“The deposition rates of viruses are huge, but still we need to determine what type of viruses and their viability to infect their hosts,” Reche told Newsweek.
The team published their findings in the journal International Society for Microbial Ecology.