Saturday, 7 March 2015

How the Limeys beat Scurvy. Eventually

At a recent workshop on healthcare, a speaker quoted Professor Dermot Kelleher, Dean of Imperial College London:

If we did what we know and did it well, we would have a 20-30% improvement in patient outcomes.

It’s particularly striking that this view was expressed by Kelleher, who has won an international reputation as a researcher in medicine. Because what he seems to be saying is that sometimes we could achieve as much progress in medicine by just taking the knowledge we already have, without expensive research, and making sure we use it everywhere.

One of the best illustrations is in the treatment of Scurvy. It took a long time to get the research done. And we were slow to extend best practice. 

Scurvy used to be a major scourge among populations deprived of sources of vitamin C. Most notably, it affected sailors who were away from land for long periods of time and therefore deprived of fresh fruit and vegetables. Estimates suggest that as many as 2 million sailors died between 1500, as the age of European discovery got under way, and 1800 when an effective method of prevention was finally adopted.

It seems Scurvy was the main cause of the death of 116 out of 170 of Vasco da Gama’s crew, 208 out of 230 of Magellan’s and 1400 out of the 1900 the Royal Navy's George Anson took with him to circumnavigate the globe in the 1740s.

Yet already in 1593, a British Admiral was recommending the drinking of orange or lemon juice as a means of avoiding the disease. 

John Woodall: pioneer in the treatment of Scurvy
And one of the first to make a fortune from Pharmaceuticals

Then in 1614, John Woodall, surgeon-general of the East India company, published his handbook for apprentice ship’s surgeons, where he advocated combating Scurvy with fresh food, citrus fruit juices, or failing any of those, sulphuric acid: he shared the popular view of a time before the vitamin was known, that it was the acid element of citrus juices that produced the benefit.

Incidentally, Woodall became wealthy stocking medicine chests for the ships, proving that big Pharma has been an excellent business to be in for a long time now.

When the story gets most interesting is nearly a century and a half later, with the arrival on the scene of James Lind. While serving as a surgeon on HMS Salisbury in 1747, he treated twelve sailors who had been afflicted with Scurvy after two months at sea. He divided them into six groups of two, each receiving a different treatment (one of them being sulphuric acid). Only the two receiving citrus juice showed real benefit from the treatment, one of them fully fit to return to service and the other nearly recovered before the fruit ran out. The only other group to show improvement were the two being treated with cider.

Lind’s experiment is now generally seen as the world’s first ever clinical trial. Nowadays, we’d probably want slightly bigger groups than two, of course. Still, at least it was a serious empirical test.

James Lind. The world's first clinical trial
showed the efficacy of citrus fruit juice against Scurvy
It was greeted by the medical profession ashore in exactly the way one would expect such a trial to be received: medics stuck to their old view that Scurvy was a disease of “putrefaction” best treated by giving the body a bit of a fillip with such compounds as sulphuric acid.

Eventually, in 1794 senior officers were successful in demanding a daily ration of two-thirds of an ounce of lemon juice, apparently just about enough to provide the daily intake of Vitamin C required, for the crew of HMS Suffolk on a passage to India. Over the 23-week crossing, not a single crewman developed Scurvy.

The following year, the use of citrus juice became official policy throughout Royal Navy. By 1800 problems of supply had been resolved so that it could be made compulsory. Because the juice was often extracted from limes, it became quite common to refer to Brits as “Limeys” over the next century or two (perhaps occasionally with affection).

Five thousands sailors a year were dying of Scurvy. And yet John Woodall’s handbook was published in 1614. Even after James Lind’s clinical trial of 1747, it took another 48 years before the practice of using citrus juice became officially adopted, and then only in Britain.

That time lapse represents nearly quarter of a million lives lost to a disease whose treatment was known.

A good story, isn’t it? Doesn’t it make the point clearly about the need for good research? And even more strongly, for doing what we already know, doing it well, and doing it now?

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