'I realise my whingeing sounds rather feeble compared to the fate of, say, poisoned former KGB spies, but I remain perturbed'

Let's meet for lunch, said my friend. I put them off, pleading a cold, as I did not want to sneeze my way through a pricey gastropub meal that I would not be able to taste.

That was annoying enough. I quite often feel under the weather at weekends for reasons I cannot quite put my finger on, though I think it could be a mini form of end-of-term-itis. Might the prospect of some time off work encourage my immunity system to put its feet up, too?

I have written before about my non-scientific diagnosis of this condition, where tired bodies succumb to bugs and germs. I think it might be a sign that I should take a holiday.

But what happened next was worse. Instead of waking up with a blocked-up nose I emerged from my slumber nauseous and dizzy and proceeded to spend most of the day feeling sick, being sick or sleeping in a bid to prevent being sick some more.

(I have been asked at this point to say thank you to Mr Dent, who made a patient and caring nurse. Even making your own green tea is no fun when you are poorly).

Thankfully my indisposition lasted only a day. I realise my whingeing sounds rather feeble compared to the fate of, say, poisoned former KGB spies, but I remain perturbed.

Apologies to readers who are half way through their lunch, but if there is one thing worse than not being able to keep a glass of water down, it is not knowing the reason why.

I remain baffled about the cause of my ruined weekend. It was not a hangover, I had not eaten anything, I think, that could be construed as likely to give me food poisoning, and there are no little Dents on the way.

As I recall I spent the day before I was taken poorly having coffee with friends in a café near the ridiculously popular Borough market in south-east London.

By strange coincidence, the last time I was struck down by a bug I had, the day before, met the same friend in the same café

But unless my friend does not wash her hands I am sure that is just a coincidence.

Any explanations, readers?