Paul Elie in The New Yorker:
In retrospect—in the rueful retrospect we are living in already—we’ll say that the virus was there all along, in the circumstances that enabled it to spread. It was there in a globally integrated society of travel, work, and commerce, the connecting and conveying powers of which far outstripped the capacity of our health systems to deal with their effects and challenged our willingness to reckon with the downsides of such integration. But it was there, too, in the language and imagery of viruses, which has been commonplace in our society for a couple of decades now—so much so that the ubiquity of virus as metaphor may have left many of us unprepared to recognize and fear the lethal literal viruses circulating among us, and to prepare ourselves and our societies against them.
It was there in the computer virus: the notion that the snags and missed connections and bits of botched code in our computers behaved virally, spreading through the system, or the network, to countless individual machines. So we bought and installed virus-protection software and watched as it was updated, showing us, in a little onscreen box, how many tens of thousands of viruses it had successfully blocked.