If you like to start out your day by opening your window for a big breath of fresh air you might want to rethink your habits a bit. A new study reveals that viruses are raining down from above on a non-stop basis, no matter where you live on the planet. As it turns out, Earth is kind of a gross place.
The research, which was published in the International Society for Microbial Ecology Journal, found that Earth’s atmosphere is really, really good at transporting viruses all over the planet. Hundreds of millions of viruses are pushed skyward by winds and carried aloft for thousands of miles before tumbling back down on whatever and whoever happens to be hanging out below. Neat!
“Every day, more than 800 million viruses are deposited per square metre above the planetary boundary layer—that’s 25 viruses for each person in Canada,” University of British Columbia virologist Curtis Suttle explains. “Roughly 20 years ago we began finding genetically similar viruses occurring in very different environments around the globe. This preponderance of long-residence viruses traveling the atmosphere likely explains why — it’s quite conceivable to have a virus swept up into the atmosphere on one continent and deposited on another.”
The researchers gathered samples from a high altitude by traveling to the Sierra Nevada mountain range in California. There, they found billions of viruses and bacteria that were riding high, many of which are thought to have been pushed skyward by powerful ocean sprays. The viruses and bacteria then fall back to Earth, often thanks to weather events like rain or even dust clouds. The biological bits are often carried in the troposphere, which the researchers note is below the stratospheres where commercial jetliners cruise but higher than the clouds.
Obviously, the viruses floating high above our heads and eventually landing all around us aren’t all bad. The vast majority aren’t capable of attacking human cells anyway and most viruses that are simply come and go before we even notice them. As for bacteria, our bodies are havens for all kinds of bacteria that do us no harm whatsoever. Scientists have estimated that the average human body is home to as many as 100 trillion bacterial cells, many of which we couldn’t live without.