When I first heard that a new coronavirus was hurtling towards Europe, I thought about John Snow. Snow was an early anaesthetist (he administered chloroform twice to a grateful Queen Victoria during childbirth) but during the cholera outbreak of 1854, he became a kind of “disease detective”, investigating London’s slums to determine how it was spreading.
Suspecting that it was transmitted through water, he scrutinised the victims’ drinking supplies. In about two days, he discovered that contaminated water from a pump was killing Soho’s residents.
Coronavirus is not cholera. Cholera is bacterial, and proliferates in a completely different way. But the meticulous work of locating victims and recording their movements is still the gold standard for halting the spread of pandemics.