Researchers at the University of California have discovered evidence of free will in flies. According to the reports, it implies that these insects choose to be pests. Perhaps this explains why a patient I once saw with tinnitus, “Like a fly’s trapped in there, doctor”, turned out to have, well, a fly trapped in there.

Just in case that has you squirming over your breakfast, I should add that another recent news item told of a boy who reported a “creepy-crawly feeling” in his ear canal. He was cured by his GP flushing out two spiders.

Not that such infestations are especially rare: take scabies and pubic lice, for example. In fact, you can take them anywhere but my consulting room. Even more exotically, GPs occasionally encounter cutaneous larva migrans in returned travellers. This itchy, linear rash looks like it is caused by the slow writhing of a worm under the skin. Because it is.

Then there’s the tiny Amazonian fish that climbs up a swimmer’s urethra and does something so unspeakable that, by comparison, being eaten by piranhas is a picnic.

OK, I’ve never treated a case of this, but it has put me off skinny-dipping.

These days, though, creepy-crawlies are as likely to be therapeutic as pathological. Leeches are being used for everything from arthritis to reconstructive surgery. Sufferers of inflammatory bowel disease apparently gain relief by swallowing pig whipworms. This interesting approach is not quite as interesting as the question, who had the idea in the first place?

Then, of course, there are maggots. Green-bottle larvae can successfully treat MRSA-infected leg ulcers, a fact that would have had you exclaiming “Wow!” had you not already been busy going, “Eeeuuuurrrggghhh!”

Compliance could be a problem, though. I have enough trouble persuading my patients to swallow pills or rub on creams, so advice that they should neck whipworms or apply maggots is likely to fall on deaf ears, and not just because they’re full of flies.

But insects aren’t the main pest in the average GP’s surgery. There’s another persistent irritant life form that causes an annoying buzzing in the ear, by complaining that she has had to wait two weeks for an appointment and the antibiotics haven’t worked. Has anyone got a really big swat?

Dr Copperfield is an Essex GP. He also writes for Doctor magazine

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