If your stomach has now settled post-Christmas, you may be ready for the final instalment of the most disgusting diseases in the world. Those who were born a lot longer ago than yesterday may notice that it’s in the same vein for which the late lamented Punch magazine was known.

Should you fancy a condition that goes the distance, consider keeping a pet worm like dracunculus medinensis, aka the Guinea worm. The best place to pick one up is in Africa with your drinking water. Maintenance is dead easy. There’s no need for an aquarium, hutch, or a garden, as it lives just under the skin.

I remember one patient who had his worm for so long that he named it Ali, which seemed the best bet as he couldn’t tell if it was male or female. Ali kept him company for some time, forming little red bumps all over him, until the day she (as we discovered) tried to escape through a huge blister on his arm.

When the blister finally burst, the little dracunculus poked through. Ali turned out to be several feet long. She had to be wrapped around a stick and pulled out gently to avoid breaking her during her outward journey which took two and a half weeks. Bon voyage, Ali!

You needn’t leave these shores to catch something sensational. Syphilis is all Columbus’s fault since, or so the story goes, his sailors brought it back to Europe in 1493.

An epidemic of syphilis spread from Naples throughout Europe in the 16^th century. The English and Italians called it the French disease, the French called it the Neapolitan disease, and pretty well everyone thought of it as the Great Pox because smallpox was small potatoes by comparison.

Syphilis is far more contagious than leprosy, as just a few minutes in a shared bed will do. A bed may even be superfluous. One man, inspired by notices in public WCs, claimed to have caught the infection in the loo. “That’s a filthy place to take a woman,” replied the consultant.

Syphilis can mimic anything from tonsillitis to athlete’s foot. It all depends on the stage of the infection.

Early syphilis can be just a painless ulcer called a chancre (pronounced Shankar, which is most unfair on Ravi and family). A few months later, the secondary stage produces symptoms like fever, headache, general malaise, aches and pains, mouth ulcers, enlarged lymph nodes, and rashes. Of course, that’s pretty much what everyone goes to the GP with.

Late syphilis takes years to develop, and it’s downhill from there. Nerves in the legs no longer transmit signals about position, which is one cause of the stomping gait you can see all over London. It also makes you fall into the handbasin when you close your eyes to wash your face. If very wobbly, you may fall into the toilet unless you’ve closed it.

No account of dreadful diseases would be complete without that scourge of the western world that has medics clamping their hands over their mouths and recoiling in horror. You may not be able to get a hospital referral, or, if you do, you’ll find yourself being bundled out of the clinic as soon as possible, usually while you’re still talking, so that the consulting room can be fumigated forthwith.

They may offer you surgery, but you may not live long enough to get to the top of the waiting list. Should you manage to reach the operating theatre, the procedure is likely to be relegated to the most junior doctor because nobody else wants to do it. Blood and pus often pour out, and the hapless trainee surgeon may throw up as a result. The patient has it relatively easy by now, as the whole gory mess is soon tidy and bandaged.

Unfortunately, this unsavoury condition is on the increase. Experts call it IGTN and claim that it spreads via shoe shops. It will impair games of footsie-footsie. It may even interfere with walking.

Like many disfiguring conditions, IGTN has a long incubation period. As I’d like you all to enjoy a healthy and happy New Year, I believe the public should be told more about this disorder. I particularly look forward to the day when every pair of winkle-pickers carries the government health warning Wearing shoes may cause ingrowing toe-nails.