The common cold is one of those illnesses that’s so, well, common, it feels like it’s just part of being human. But it turns out camels might actually be at least partially to blame for our winter coughs and sniffles. According to a recent study in Proceedings of the National Academy of Sciences, HCoV-229E—one of the four coronaviruses associated with the common cold—may have originated in camels and spread to humans a mere 5000 years ago.
Scientists at the German Center for Infection Research were researching the more insidious Middle East Respiratory Syndrome (MERS) coronavirus when they made their common cold discovery. Like the common cold—a catchall term for upper respiratory infections caused by some 200 viruses, most of which are rhinoviruses and coronaviruses—MERS messes with our respiratory tract, but unlike the common cold, it can cause infections that sometimes prove fatal. Researchers had a hunch that MERS originated in camels and were testing 1000 camels for the virus. They discovered pathogens related to HCoV-229E in nearly 6 percent of the animals.
They suggest African bats originally passed the virus to camels before it leaped to humans. (They also note there’s a chance another host, possibly bats, passed the virus directly to humans, but that it's unlikely.) Because camels weren't introduced to Africa from the Middle East until about five millennia ago, the transmission of the HCoV-229E-related virus had to have taken place after that, the researchers say.
While the discovery that the common cold may have come from ancient camels is certainly interesting, the study also has important implications for MERS research. Scientists hope that by researching the spread and evolution of this coronavirus, and the ways the human immune system reacts to it, they might gain important insights into MERS and determine the likelihood of an epidemic. “Our current study gives us a warning sign regarding the risk of a MERS pandemic—because MERS could perhaps do what HCoV-229E did,” explains researcher Christian Drosten. “Fortunately, the virus has not adapted well enough to humans, and has consequently been unable to spread globally up to now.”