Viruses have spent billions of years perfecting the art of surviving without living — a frighteningly effective strategy that makes them a potent threat in today’s world.
That’s especially true of the deadly new coronavirus that has brought global society to a screeching halt. It’s little more than a packet of genetic material surrounded by a spiky protein shell one-thousandth the width of an eyelash, and leads such a zombielike existence that it’s barely considered a living organism.
But as soon as it gets into a human airway, the virus hijacks our cells to create millions more versions of itself.
There is a certain evil genius to how this coronavirus pathogen works: It finds easy purchase in humans without them knowing. Before its first host even develops symptoms, it is already spreading its replicas everywhere, moving onto its next victim. It is powerfully deadly in some but mild enough in others to escape containment. And, for now, we have no way of stopping it.
As researchers race to develop drugs and vaccines for the disease that has already sickened 350,000 and killed more than 15,000 people, and counting, this is a scientific portrait of what they are up against.
‘Between chemistry and biology’
Respiratory viruses tend to infect and replicate in two places: In the nose and throat, where they are highly contagious, or lower in the lungs, where they spread less easily but are much more deadly.
This new coronavirus, SARS-CoV-2, adeptly cuts the difference. It dwells in the upper respiratory tract, where it is easily sneezed or coughed onto its next victim. But in some patients, it can lodge itself deep within the lungs, where the disease can kill. That combination gives it the contagiousness of some colds, along with some of the lethality of its close molecular cousin SARS, which caused a 2002-2003 outbreak in Asia.