On Finishing David Quammen's "Spillover: Animal Infections and the Next Human Pandemic"

So I’ve finished David Quammen’s excellent new book of nonfiction, Spillover: Animal Infections and the Next Human Pandemic, about zoonotic viruses and the danger we face from new pandemics originating in crossover viruses leaping from animals to humans. At 520 pages, it’s a detailed and impressive read. Like other long nonfiction books on ecology or natural science I’ve read this year (Alex Prud’homme’s The Ripple Effect comes to mind), it takes a time commitment, and I felt like I should get a merit badge when I reached the last page. But the merit badge of Spillover is found in the organization of the book itself. In some ways he saved the best for last. The penultimate chapter is a fascinating (and minutely detailed) investigation/explanation of the origin of the HIV virus, a story with many twists and turns. I won’t go into it here, but I was surprised to learn that scientists now believe the virus actually originated (the “spillover” event from animals to humans, in this case believed to have occurred some time in the act of killing/eating a monkey or chimpanzee) in 1908, more or less. It also ends with this fascinating observation: Quammen quotes several scientists who describe the population boom of humans in the last century as being an “outbreak,” similar to other species outbreaks, when they suddenly swell in population over a short period of time. With insects, it might be a year or two. With humans, it’s occurred within a matter of decades: “From the time of our beginning as a species (about 200,000 years ago) until the year 1804, human population rose to a billion; between 1804 and 1927, it rose by another billion; we reached 3 billion in 1960; and each net addition of a billion people, since then, has taken only about thirteen years. In October 2011, we came to the 7-billion mark and flashed past like it was a ‘Welcome to Kansas’ sign on the highway. That amounts to a lot of people, and certainly qualifies as an ‘explosive’ increased within Berryman’s ‘relatively short period of time'” [my note: the definition of an outbreak] (496).
That’s where Quammen weighs in, with the threat of virus as a possible end to our outbreak: “We are prodigious, we are unprecedented. We are phenomenal. No other primate has ever weighed upon the planet to anything like this degree. In ecological terms, we are almost paradoxical: large-bodied and long-lived but grotesquely abundant. We are an outbreak. And here’s the thing about outbreaks: They end. In some cases they end after many years, in other cases they end rather soon. In some cases they end gradually, in other cases they end with a crash” (497-8).