If the American elections were to be won on complexions, Al Gore would be home and dry. Smooth, pink, shiny, flawless - his skin was a story of success as he went to the cinema last weekend.

In contrast, his rival for the presidency, George W Bush, relaxing on Prairie Chapel Ranch, sported a large plaster on his right cheek, running vertically down his face an inch or so from his ear.

Not the sort of blemish to be covered by spot concealer - too bulbous, too lumpy. The plaster didn't sit flat against the skin, it couldn't quite hide what was underneath. Poking out from the side, bulging up into the pad of the plaster was a red, angry boil, refusing to be concealed. No wonder Bush was keeping a low profile. To develop a boil - on your face of all places - while an election hangs in the balance, is unfortunate, to say the least.

So what exactly is Bush suffering from? Quite simply, a boil, or skin abscess, is an infection deep in the skin which usually occurs if bacteria get into a deep break in the skin, which can be caused by an ingrown hair, or a splinter, acne, or a blocked sweat or oil gland.

They are more common in people with diabetes, kidney failure or immune deficiency, and when a large number of boils form close together, the mass is called a carbuncle. Most boils will drain on their own, but larger ones may need to be lanced by a health-care professional. Occasionally, antibiotics may be needed.

They're miserable, and embarrassing. But why? The technical word for a boil is furuncle, which has its origins in the Latin word furunculus, meaning petty thief, suggesting perhaps that the poor, the dirty, the undernourished are more likely to suffer.

They ooze and suppurate in the pages of William Shakespeare and Ben Jonson and the Bible - festering boils were the ninth plague on Egypt, according to Exodus. Job, whom "Satan smote with sore boils from the sole of his feet unto the crown" suffered from them, Oliver Cromwell suffered from them.

Throughout most of his adult life Karl Marx was tormented by boils, which were particularly prevalent when he was writing Das Kapital, which he wrote in a fit of spleen, in the hope of destroying capitalism and undermining existing society.

Such was the work's destructive potential, he suspected there was some mysterious link between it and his boils. As if his inner impulses had somehow taken shape on his skin in the form of festering sores and seeping lumps.

So Bush is in good, if not like-minded company. Keep putting on the plasters, George.