Spillover: Animal Infections and the Next Human Pandemic

Many of Quammen’s subjects are infected with zoonotic diseases accidentally. A young veterinarian from Cairns became infected with Hendra while not wearing gloves, due to the rapidly changing circumstances of her house call to a sick horse. As Quammen describes, “The protocol was to use gloves for a postmortem, but not for live animals. Then the one situation led so swiftly to the other,” and it was late at night, in bad weather, when “it’s not always easy to take the proper precautions” (47). Working in nature with animals is unpredictable, like zoonotic disease itself. The young veterinarian became infected with Hendra and is one of the two known survivors. Her accident is one of several in Quammen’s narrative where a split-second decision, or accident, results in illness or near disaster. Kelly Warfield’s three weeks in quarantine, and the deaths of the two Russian scientists working on Ebola treatment, are two other notable examples.

Aleksei Chmura is one of Quammen’s key examples of a risk taker. There is no food he refuses to eat, and when Quammen tries to draw a boundary, Chmura says, “You’d have to test me by putting human flesh in front of me” (198). Chmura takes a similar posture on the subject of wearing full containment safety gear to catch bats to test them for SARS: It would be safer to wear masks and other equipment, but that would also inhibit the work. To quote Chmura again, “that’s not very practical” (201). Similarly, Kelly Warfield’s hands were not fully protected for her Ebola work because they “had to remain delicately dexterous” (103). To do the work that may help make others safe from zoonosis, scientists must take risks. It would also be impossible to avoid risk entirely because animals are unpredictable. Like spillover, laboratory work is a combination of deliberate choice and random chance, all of it potentially dangerous for humans. 

This is perhaps Quammen’s most persistent theme. He begins his narrative with the reminder that “humanity is a kind of animal, inextricably connected with other animals: in origin and in descent, in sickness and in health” (14). The language here deliberately echoes that of a wedding: The bonds between humans and other animals proves even more impossible to break, as Quammen’s many case studies of zoonosis show. This also has emotional components, as in Prosper Balo’s grief for his gorillas and Jane Goodall’s persistent concern for the chimps of Gombe.

Humanity’s animal status is in some ways cause for concern and anxiety, as Quammen notes when he calls humanity an “outbreak,” since no outbreak is infinite. Indeed, one of the consistent preoccupations of Quammen’s experts, for all their various specialties, is the “Next Big One,” and there is agree among them that it will be zoonotic (512). Humans are bound by ecology even as they consistently transform it to reshape their needs, and humanity’s relationship to animals could result in catastrophe. Quammen’s only antidote for this is the human capacity for planning and intelligence, unique in the natural world.