David Quammen
The latest scary new virus that has captured the world’s horrified attention, caused a lockdown of 56 million people in China, disrupted travel plans around the globe and sparked a run on medical masks from Wuhan, Hubei province, to Bryan, Texas, is known provisionally as “nCoV-2019”. It’s a clunky moniker for a lurid threat.
The name, picked by the team of Chinese scientists who isolated and identified the virus, is short for “novel coronavirus of 2019”. It reflects the fact that the virus was first recognised to have infected humans late last year — in a seafood and live-animal market in Wuhan — and that it belongs to the coronavirus family, a notorious group. The Sars epidemic of 2002-3, which infected 8,098 people worldwide, killing 774 of them, was caused by a coronavirus, and so was the Mers outbreak that began on the Arabian Peninsula in 2012 and still lingers (2,494 people infected and 858 deaths as of November).
Hong Kong medical workers hold a strike near Queen Mary Hospital demanding the city close its border with China to reduce the coronavirus spreading, on February 3, 2020.
Despite the new virus’ name, though, and as the people who christened it well know, nCoV-2019 isn’t as novel as you might think.
Something very much like it was found several years ago in a cave in Yunnan, a province roughly a thousand miles southwest of Wuhan, by a team of perspicacious researchers, who noted its existence with concern. The fast spread of nCoV-2019 — more than 17,000 confirmed cases, including at least 350 deaths, as of Tuesday morning, and the figures will have risen by the time you read this — is startling but not unforeseeable. That the virus emerged from a non-human animal, probably a bat, and possibly after passing through another creature, may seem spooky, yet it is utterly unsurprising to scientists who study these things.
We disrupt ecosystems, and we shake viruses loose from their natural hosts. When that happens, they need a new host. Often, we are it.
One such scientist is Shi Zhengli, of the Wuhan Institute of Virology, a senior author of the draft paper (not yet peer reviewed and so far available only in preprint) that gave nCoV-2019 its identity and name. It was Shi and her collaborators who, back in 2005, showed that the Sars pathogen was a bat virus that had spilled over into people. Shi and colleagues have been tracing coronaviruses in bats since then, warning that some of them are uniquely suited to cause human pandemics.
Why Wuhan virus is the most dangerous coronavirus
In a 2017 paper, they set out how, after nearly five years of collecting faecal samples from bats in the Yunnan cave, they had found coronaviruses in multiple individuals of four different species of bats, including one called the intermediate horseshoe bat, because of the half-oval flap of skin protruding like a saucer around its nostrils. The genome of that virus, Shi and her colleagues have now announced, is 96 per cent identical to the Wuhan virus that has recently been found in humans. And those two constitute a pair distinct from all other known coronaviruses, including the one that causes Sars. In this sense, nCoV-2019 is novel — and possibly even more dangerous to humans than the other coronaviruses.
I say “possibly” because so far, not only do we not know how dangerous it is, we can’t know. Outbreaks of new viral diseases are like the steel balls in a pinball machine: You can slap your flippers at them, rock the machine on its legs and bonk the balls to the jittery rings, but where they end up dropping depends on 11 levels of chance as well as on anything you do. This is true with coronaviruses in particular: They mutate often while they replicate, and can evolve as quickly as a nightmare ghoul.
The virus trail from the past will stretch to the future
Peter Daszak, the president of EcoHealth Alliance, a private research organisation based in New York that focuses on the connections between human and wildlife health, is one of Shi’s longtime partners. “We’ve been raising the flag on these viruses for 15 years,” he told me with calm frustration. “Ever since Sars.” He was a co-author of the 2005 bats-and-Sars study, and again of the 2017 paper about the multiple Sars-like coronaviruses in the Yunnan cave.
Daszak told me that, during that second study, the field team took blood samples from a couple of thousand Yunnanese people, about 400 of whom lived near the cave. Roughly 3 per cent of them carried antibodies against Sars-related coronaviruses.
When the dust settles, that nCoV-2019 was not a novel event or a misfortune that befell us. It was — it is — part of a pattern of choices that we humans are making.
“We don’t know if they got sick. We don’t know if they were exposed as children or adults,” Daszak said. “But what it tells you is that these viruses are making the jump, repeatedly, from bats to humans.” In other words, this Wuhan emergency is no novel event. It’s part of a sequence of related contingencies that stretches back into the past and will stretch forward into the future, as long as current circumstances persist. So when you’re done worrying about this outbreak, worry about the next one. Or do something about the current circumstances.– GN
