Diary of a Primary School Mum: 'It's a miracle teachers aren't off sick more'

There very nearly wasn't a diary. There very nearly wasn't a Mummy to write it, when a quick penny spent in a restaurant toilet ended up in false imprisonment. Despite much lock-twisting, handle-yanking and door-kicking, stuck was the word. The situation took hours to rectify, by which time concerns about school drop-offs and pick-ups (and that Sex and the City: The movie would never be seen) were at fever pitch. Highlight of the evening was fellow diners' round of applause once mission to free had finally been accomplished.

It's a wonder more teachers don't need rescuing with the hotbed of disease they face on a daily basis. Worms, slapped cheek syndrome, norovirus, emphitigo, Molluscum contagiosum – a school could compile its very own ailment almanac. Miss Perry came to find me in the playground. "I just wanted to check," she asked politely, "that Claire's eyes are all right. It's just there's been a lot of conjunctivitis around recently and it spreads like wildfire."

Miss Perry was reassured that while there was indeed some crust underneath the clear whites of my daughter's eyes, it was leftover sleep that I'd been too lazy to clear away, as opposed to any infection. "It's a miracle," Miss Perry confided (tapping her skull in the absence of timber), "that I've never picked anything up. Not even nits."

Don't mention the 'n' word. Spine-tingling crawlers that would probably even survive a nuclear holocaust, they just won't leave Reception alone. The only school I've heard that deals with them properly isn't the twins' one, it's a faith school my friend's children go to. A hardcore approach (perhaps lice are against their religion) means that all pupils have their hair checked twice a term and any child found with the blighters is sent straight home with the contact details of this local scientist woman specialising in nit obliteration. For £25 she painstakingly works through a child's hair, before covering it in a superior overnight product and shower cap. Job satisfactorily completed or money-back guarantee. "But £25 is very expensive," I protest. "Believe me," my friend reassures, "once nits work their way through a family and you've tried every last lotion and potion to get rid of them, £25 is a bargain."

My best friend is a primary school teacher. I'm round at hers for dinner – it's safer than going to a restaurant. "How come you're not ill more often," I ask, "considering the hotbed of disease you face at work?" Her laugh's polite, but I can tell she thinks I'm a drama queen. "Seriously," I continue, "it's a miracle teachers don't have more days off sick. "Ah," my friend confides, "that's because we all wait for the holidays to get ill. It's only when we finally stop that our immune systems betray us."

"What about nits," I say, the topic of conversation quite ruining the spaghetti bolognese. "Ever caught those from a pupil?" She puts down her fork, slams a palm on the table and boasts a vehement, "NO."

It was lucky for my friend that the table was made of pine. At pick-up the next afternoon, the danger of not touching wood when uttering that phrase is all too apparent.

The whites of Miss Perry's eyes are streaked red and a smearing of gunk gives it away. At home I catch Claire pawing her eyes with alarming vigour. "Are you hands clean?" I ask sharply. "Otherwise you'll have conjunctivitis before you know it."

"I'm sorry Mummy," she apologises. "It's just I'm always so tired after school that I'm afraid I just can't help it."