I’m always cheered when I read those stories that reveal there are more germs on your beard / phone / J-Cloth / towel than your toilet seat.

Not because of the ill-founded confidence in my toilet hygiene (or my ability to grow a beard) but rather the knowledge that, despite the tumult of mean-minded bacteria on most household objects, mostly we don’t drop down dead.

We’re built for this sort of thing. Evolution has figured it out. When a mother kisses her baby, she samples the pathogens on the tot’s skin. She ingests them, uses her own immune system to develop antibodies that she then delivers back to her baby through breast milk. Nifty eh?

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I’m a great believer in dirt as a boon companion. Give every child a peanut, a lump of soil, a pork pie and a grubby friend to lick and the risk of future ailments will recede. Chuck ’em in a mucky puddle, I say. Score those kneecaps with filthy Brillo pads. Take a tipple of swimming pool water before bed.*

This week I saw off my mattress with a teary farewell. I dread to think how long “ol’ baggy springs” has been my bedtime co-pilot of choice but I guess it could safely buy a beer without ID.

I changed the mattress not because of the frenzy of fast-evolving mites feasting on my all-you-can-eat skin cell buffet but because it had become a back-breaker.

Had the springs stayed true and my slumber unimpaired, the mattress and I would have co-existed in simple harmony, to the extent that, come my last breath, we would have been indistinguishable one from the other, scientifically speaking.

*Seek medical advice. My wisdom has yet to be recognised as a qualification.