I came down with chickenpox only at the grand old age of 29.
For decades, I had thought I had natural immunity against the varicella zoster virus, because as a teenager, I had slept in the same bedroom as my sister during her bout of chickenpox and had escaped unscathed. So I did not think I needed vaccination.
When I was actually afflicted, I was lucky to have taken antiviral medication early, so the experience was not too agonising.
Nonetheless, it gave me much anxiety. Would I recover in less than two weeks, in time for my overseas holiday? Would I be left with scars from the blisters that I had scratched and burst despite my best efforts not to do so?
At the time, I regretted not having received the preventive jab.
But as things all worked out well in the end, inertia and complacency have set in again.
My last immunity-improving injection was a booster shot of the Bacille Calmette-Guerin (BCG) vaccine against tuberculosis at the age of 12. This was before booster shots were stopped in 2001.
I have not bolstered my body to battle hepatitis B, having been born before hepatitis B vaccination was included in the national childhood immunisation programme in 1987.
I have not been inoculated against influenza, even when I travelled to temperate countries in winter, while the virus is rampant.
Needles do not paralyse me in panic, but I am not partial to being poked by sharp spikes. The last factor that gives me pause is a fear of possible side effects.
But as age advances, perhaps it is time to protect myself, rather than to pray for providence.
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