I used to persuade soldiers to get their regular immunizations by claiming that that wars have been lost as a result of poor preventive medicine, with infectious disease, poor sanitation, and immunizations crippling many an army. In fact, as I read last night, it's quite possible that America might not have won its independence had the British actually took steps to ensure the health of their sailors.
Most Americans know about the American Revolution from grade-school history books, where we learned of thrilling battles at Bunker Hill, Trenton, Saratoga, and finally, at Yorktown. Yet, like many insurgencies, the war was not won on the battlefield; Washington's Continental Army lost more military battles than they won.
True, the Continental Army owed much of their success to the strategic posturing of France, and overextension on the part of the British armed forces. After all, the Royal Navy in particular was far too small to cover the breadth of the British Empire. Tasked with protecting assets stretching from the home waters of the English Channel, the Carribbean, and the Mediterranean, the Royal Navy was hard-pressed to sustain a blockade off the American coastline, while simultaneously containing the Bourbons (then the ruling power in both France and Spain).
Although Britain successfully undertook a prodigious ship-building effort, her real difficulty lay in recruiting and retaining enough sailors to man ships-of-the-line, frigates, and corvettes. In October 1778, over ten percent of the Royal Navy's ships-of-the-line lacked the sufficient manpower to put to sea.
These difficulties were compounded by the fact that, though the Royal Navy drafted some 170,000 sailors into service, over 40,000 deserted. Furthermore, another 18,000 sailors--fifteen times the number which perished in battle--succumbed to disease, with scurvy being one of the primary culprits.
Europeans had known of a correlation between the consumption of citrus fruit and the prevention of scurvy since the time of the explorer Vasco de Gama in the late 15th Century. Later, in 1747, the physician James Lind formally documented the link between citrus and scurvy, even proposing a method of preserving lemon juice for long voyages. Indeed, in 1775, as war was breaking out in the Americas, Captain James Cook of the Royal Navy circumnavigated the globe without losing a single man to scurvy, relying on sauerkraut as a source of Vitamin C. Yet the British were slow to adopt regular Vitamin C consumption, and their naval operations suffered greatly. Nearly one-third of British sailors were hospitalized in 1779.
Scurvy hamstrung the Royal Navy's operation. Upon France's entry into the war, the British Channel Fleet was thoroughly unable to venture from their home port and provide a consistent blockade of the French port of Brest, a mere 150 miles from Britain. Scurvy caused horrendous attrition among the sailors of the Royal Navy, forcing the British to conduct their blockade from anchorage off the southern coast of England. This permitted a convoy of French frigates and troop ships, led by Charles Hector, Comte d'Estaing, to slip past the British blockade and land a sizable force in the Colonies.
In 1795, over a decade after the British surrender at Yorktown, Sir Gilbert Blaine petitioned the Admiralty to regularly issue lemon juice to British sailors. Within a few years, sickness in the Royal Navy dropped precipitously, with hospitalization rates dropping from one in three in 1779 to one in twenty by 1807.
A healthier force was able to leave Britain and seal off the French coast through long-standing blockades. It was the ability to stay at sea longer, according to British historian Piers Mackesy, which allowed the British to break the naval power of Napoleon.
Which raises the question: would we be living in a far different world had the British had simply taken their vitamins?