Quotes from David Quammen

R0 explains and, to some limited degree, it predicts. It defines the boundary between a small cluster of weird infections in a tropical village somewhere, flaring up, burning out, and a global pandemic. It came from George MacDonald.

Viruses face four basic challenges: how to get from one host to another, how to penetrate a cell within that host, how to commandeer the cell's equipment and resources for producing multiple copies of itself, and how to get back out—out of the cell, out of the host, on to the next. A

The purpose of this book is not to make you more worried. The purpose of this book is to make you more smart.

Als de hemel donker wordt met zwarte donderwolken, de grote bomen zwaaien in de wind, de pauwen zingen, hunker ik ernaar terug te rennen naar Gir.

Lyme disease, psittacosis, Q fever: These three differ wildly in their particulars but share two traits in common. They are all zoonotic and they are all bacterial.

Horses aren't native to Australia. They are exotic, first brought there by European settlers barely more than two centuries ago. Hendra is probably an old virus, according to the runic evidence of its genome, as read by molecular evolutionists.

Viruses face four basic challenges: how to get from one host to another, how to penetrate a cell within that host, how to commandeer the cell's equipment and resources for producing multiple copies of itself, and how to get back out—out of the cell, out of the host, on to the next.

Others are new and inexplicably sporadic, claiming a few victims (as Hendra does) or a few hundred (Ebola) in this place or that, and then disappearing for years.

So you have density, infectivity, mortality, and recovery—four factors interrelated as fundamentally as heat, tinder, spark, and fuel. Brought together in the critical measure of each, the critical balance, they produce fire: epidemic.

Another implication was that epidemics don't end because all the susceptible individuals are either dead or recovered. They end because susceptible individuals are no longer sufficiently dense within the population.

At the Chatou market in Guangzhou, for instance, he had seen storks, seagulls, herons, cranes, deer, alligators, crocodiles, wild pigs, raccoon dogs, flying squirrels, many snakes and turtles, many frogs, as well as domestic dogs and cats, all on sale as food.

You could also buy leopard cat, Chinese muntjac, Siberian weasel, Eurasian badger, Chinese bamboo rat, butterfly lizard, and Chinese toad, plus a long list of other reptiles, amphibians, and mammals, including two kinds of fruit bat. Quite an epicure's menu. And of course birds: cattle egrets, spoonbills, cormorants, magpies, a vast selection of ducks and geese and pheasants and doves, plovers, crakes, rails, moorhens, coots, sandpipers, jays, several flavors of crow.

I think the virus is present all the time, within reservoir species," he told me. "And sometimes there is transmission from reservoir species to other species.

Later in conversation he corrected himself: It was in fact 1.1 million pigs. The difference might seem like just a rounding error, he told me, but if you ever had to kill an "extra" hundred thousand pigs and dispose of their bodies in bulldozed pits, you'd remember the difference as significant.

It wasn't a petty squabble. It was a big squabble, in which pettiness played no small part.

The result will be gradual transmutation of heritable forms, and adaptation to circumstances, by a process of selective culling. Eventually he gave the crank a name: natural selection. Twenty years passed after the E notebook entry. The world heard nothing about natural selection.

if superspreaders exist and can be identified during a disease outbreak, then control measures should be targeted at isolating those individuals, rather than applied more broadly and diffusely across an entire population.

A parasitic microbe, thus jostled, evicted, deprived of its habitual host, has two options—to find a new host, a new kind of host . . . or to go extinct.

This elaborate concatenation of life-forms and sequential strategies is highly adaptive and, so far as mosquitoes and hosts are concerned, difficult to resist. It shows evolution's power, over great lengths of time, to produce structures, tactics, and transformations of majestic intricacy. Alternatively, anyone who favors Intelligent Design in lieu of evolution might pause to wonder why God devoted so much of His intelligence to designing malarial parasites.

If you look at the world from the point of view of a hungry virus," the historian William H. McNeill has noted, "or even a bacterium—we offer a magnificent feeding ground with all our billions of human bodies, where, in the very recent past, there were only half as many people. In some 25 or 27 years, we have doubled in number. A marvelous target for any organism that can adapt itself to invading us.

Every species has come into existence coincident both in space and time with a pre-existing closely allied species. Description or law, it challenged the theory of special creation and bruited the idea of evolution in a tone of thunderous innuendo.

The term refers to cascading disruptions that can pass between trophic levels—that is, between different categories of interrelated organisms in the hierarchy of energy transfer within an ecosystem.

There's no reason to assume that AIDS will stand unique, in our time, as the only such global disaster caused by a strange microbe emerging from some other animal. Some knowledgeable and gloomy prognosticators even speak of the Next Big One as an inevitability. (If you're a seismologist in California, the Next Big One is an earthquake that drops San Francisco into the sea, but in this realm of discourse it's a vastly lethal pandemic.)

Once a species of insect or bird has reached a new island and established a population, evolution toward gigantism does offer certain advantages: fat storage, thermal stability, and defense against predators, if there are any. But gigantism is also a way of becoming flightless, and flightlessness is a way of becoming marooned.