Age: At least 5,500 years old.

Appearance: A yellowish discharge from the penis, anus or vagina.

Also known as: Hot piss, the slime, the drip . . .

I feel quite sick and we've barely started. Tell me something to take my mind off it. It's more commonly known as the clap. That comes from the old French clapoir, meaning venereal sore–

This really isn't helping. Which in turn comes from clapier–

Meaning toilet seat? Meaning brothel. It's spread by unprotected sex, just like syphilis, chlamydia and pregnancy.

You can get pregnant just by having sex? Remarkable, isn't it? Gonorrhea, meanwhile, is caused by the bacterium Neisseria gonorrhoeae, which can colonise your mouth, throat and eyes, as well as your undercarriage. Symptoms include pain when urinating, swollen testicles and bleeding between periods. Untreated, it can cause infertility, ectopic pregnancy and, in rare cases, death. Mothers can pass it to their babies.

How long has this been going on? The ancient Egyptians first described gonorrhea in their papyrus scrolls. It has often been confused with syphilis, but Napoleon, Mussolini and Hitler are all believed to have caught it. James Boswell, the prostitute-loving biographer, succumbed at least a dozen times.

But why are we talking about it? It's clearly one of those picturesque diseases that only affects long-dead famous people. If only. The Health Protection Agency has just reported a worrying increase among young people. Among women, under-25s now account for 73% of new cases, while for men the figure is 41%.

Don't those rivers of pus cramp their style? Many sufferers show no symptoms. And not everyone realises it can be passed on by oral sex or sex toys.

Still, at least it's curable. Not for long, perhaps. According to one expert at the HPA, the usual antibiotic may no longer work in five years – and there is no replacement in the pipeline. "Safe sex may eventually be the only way of controlling the infection," she warns.

Do say: "No glove, no love."

Don't say: "Well, if you're sure it's supposed to be that colour . . ."