While we socially isolate, we might spare a thought for seafarers battling the main diseases that often reached epidemic proportions among ships’ crews in the Age of Sail, a period in which the ‘miasma theory’ — that disease was contracted by inhaling foul air — still prevailed. We glimpse the theory in the laments of a former ship’s doctor writing early in the 18th century, regarding unventilated ships’ holds, in which ‘stagnant salt water’ tended to accumulated, and regarding their lower decks, in which ‘a multitude of people breathing and constantly perspiring’ were crowded together. The long-held theory is reflected in the name of that well-known scourge of tropical climes including the coast of West Africa, malaria (‘bad air’), which we, of course, know is spread by mosquitoes. But before we look briefly at epidemics involving infectious diseases, let’s look at that well-known non-communicable disease, scurvy, which had a devastating impact on seamen’s health ever since long voyages came to be undertaken.
