It starts with a tick­le. A dry lit­tle throat-clear­ing sound that seems in­no­cent enough. Then, hours lat­er, the tick­le turns in­to a bark­ing, hack­ing, chest-rat­tling or­ches­tra that wakes the neigh­bours, fright­ens the pug and has your fam­i­ly won­der­ing if you’re start­ing a new pan­dem­ic. Wel­come, dear read­er, to the sea­son of the cough.

This year’s cho­rus seems loud­er than ever. Half the coun­try is cough­ing—at home, in of­fices, in taxis, in line at the phar­ma­cy. Every­one’s do­ing it: the doc­tors, the nurs­es, the pa­tients, even the se­cu­ri­ty guards at the gate. It’s as if we’re all part of an un­in­ten­tion­al choir.

And of course, every­one has their the­o­ry.