The latest coronavirus epidemic has sent people scrambling for face masks like never before. “The world is facing severe disruption in the market for personal protective equipment,” Tedros Adhanom Ghebreyesus, the director-general of the World Health Organization, warned last week. “Demand is up to 100 times higher than normal and prices are up to 20 times higher.” This, even though face masks are not, on their own, a proven prophylactic against infection from the new coronavirus (hand washing is more important, medical experts seem to agree).

And yet we shouldn’t look upon this buying spree as a sign of irrational epidemic-panic. Consider mask-wearing in its historical and cultural context, and you’ll see that in China, for example, it serves as far more than simply a means of protecting oneself from infection. Masks are also a marker of medical modernity, as well as a signal of mutual assurance that allows a society to keep functioning during an epidemic.