The day I discovered what worry was

Before I had children I don’t think I appreciated what anxiety was. I’d been anxious at various points in my life up until that point — when taking exams, for instance — but those occasions paled into insignificance when I experienced the full monty.

The occasion was the birth of my son Ludo in 2004. The delivery was fine, but it just so happened that he was born in a five-day window between Caroline being infected with chickenpox and presenting the first symptoms. That meant Ludo was exposed to a full load of the Varicella zoster virus before Caroline had had a chance to develop any of the antibodies and pass them on.

Given that newborns don’t have much in the way of an immune system, Ludo would be in some danger if he became infected. We had a difficult two weeks waiting to see if he developed chickenpox — and I remember thinking at the time that you couldn’t be any more anxious than this — and then, when he did get chickenpox, a truly awful time waiting to see if any of the anti-viral drugs would be effective. The name of the disease he’d contracted is neonatal varicella and the mortality rate is 30 per cent.

Now, I suppose it’s possible to be even more anxious than that. Perhaps the mercury rises higher when the mortal danger your children are in comes upon you suddenly — if you’re on a sailboat in the middle of the ocean that starts to sink, for instance. But I find it hard to imagine.

So what are the telltale signs that you’re in the seventh circle of hell? For one thing, you start hallucinating. When I was sitting across from Ludo’s cot, staring at the machine he was hooked up to, ready to call a nurse at the first sign of any deterioration, I began to see rats in my peripheral vision.