Breathless: The Scientific Race to Defeat a Deadly Virus

by David Quammen

In 2018, the average consumption in China was seventy-five pounds per person. But in late summer that year an outbreak of African swine fever swept into the country, eventually affecting more than 150 million pigs. The disease is caused by African swine fever virus (ASFV), a DNA virus endemic to sub-Saharan Africa, where its reservoir hosts are bushpigs and warthogs, and ticks vector the virus from one animal to another. With the arrival of European colonizers, bringing domestic swine to Africa, ASFV infected those pigs too. In the twentieth century it got to Europe, then was eradicated, then returned in this century, possibly by way of wild boar imported to southern Belgium from Eastern Europe for the amusement of hunters. Among domestic pigs, the virus is highly virulent, and the strain that reached China, by August 2018, was almost 100 percent lethal. Within eight months, because China normally produces such a large share of the world’s pigs, commodities analysts in the West were cheerily telling their industry clients that ASFV’s impact there would “lift all protein boats.”