Temper your excitement about the Covid vaccine

Ever since Giacomo Pylarini, a physician working in the Ottoman Empire, sent a report to the Royal Society in 1701 that Turkish women believed pus from a smallpox survivor could induce immunity in a healthy person – and was dismissed as a dangerous quack – inoculation has been as much an art as a science. But it has proven to be the greatest life-saver of all time, eliminating smallpox and suppressing many other diseases. In Pylarini’s prescient words, it is ‘an operation invented not by persons conversant in philosophy or skilled in physic, but by a vulgar, illiterate people; an operation in the highest degree beneficial to the human race.’

It looks like a vaccine is probably going to work against Covid. That was never guaranteed: it’s been decades since scientists started seeking a vaccine for malaria and HIV, with no luck so far, and flu vaccines only last for a limited time before the virus mutates.