Under the counter with Lindsay Calder
I think it was the moment when my husband said "we'd better give Dad power of attorney while we're away" that really did it for me. Spending a month in South America had been gradually losing its appeal ever since I'd paid for the flights.

At first I spurned Cornwall and the Costa del Sol as not exotic enough, but sod that - come rain, come grockles, come fish and chips, at least the odds are high on returning home from the holidays. I confess it was my idea to take this extended "holiday" - I'd read the guidebooks, and had no qualms whatsoever, but as soon as they get to hear of your impending trip, the holiday terrorists come out in force, and vie with each other to recount the most gruesome anecdote about your destination.

I've spent pounds 160 on vaccinations, and have so many holes in my arms that, if my body weight were halved, people would be forgiven for thinking I were a supermodel. But jabs are not enough. The favourite "you'll never guess what I caught there" illness is giardiasis. Three people have told me about it, and I don't want to know any more. I had never heard of giardiasis until a friend's boyfriend caught it. When I asked what it was, she explained in a most serious tone, "well, it's awful - you burp farts". It wasn't so much his health she was concerned about; she was most put out that she had to sit next to him on the 14-hour flight home. Others have described the condition as "Coca-Cola bottom". Please, please God, don't let me catch this.

Then, there's the infection you get if you pee into stagnant water (why you would want to, I don't know, other than because it makes a nice sound) and little micro-things swim "upstream" into your body. I was told this by a woman who is known at the company, where she is a director, as "the simple housewife", so I didn't pay much attention when she gleefully told me I must "pee through a tea-strainer". A rather more convincing source trotted out this same advice yesterday, so I'm beginning to believe it. But the most startling comment came from an alarmingly dippy lawyer I know. "Where are you going? Oh, lovely. Friends of mine went there last year. He died after week, but I think they were having a lovely time."

Look out bandits, mosquitoes and farty-breath bugs, because I have been doing some serious shopping: khaki army trousers with drawstring ankles to keep the creepy-crawlies out, pounds 19.37, from Laurence Corner. Zoom headlamp for hands-free night-time jungle ablutions, pounds 24.99; Belt Bank, a belt with interior zip to stash the cash and fool the desperados, pounds 9.99; Pur Potable water purifier, to eliminate giardiasis cysts, pounds 54.99; all from the Survival Shop. Lifestyle impregnated mosquito net, pounds 28.95; Expedition 100 (maximum strength) insect repellent, so dengue fever doesn't interfere with our itinerary, pounds 5.99; Swiss Clean wipes, to wipe absolutely everything, pounds 2.99; all from the Porter Nash Pharmacy. Emergency sterile medical kit, pounds 17.50; Immodium, box of 18 (I've got four boxes), pounds 5.99; Boots.

I don't have room for any clothes at all, now that I've packed that lot, but I've got to make space for a couple more things: a tea strainer, and a packet of extra strong mints for the flight home.

Laurence Corner, 62-64 Hampstead Road, London NW1 (0171-813 1010); The Survival Shop, 11-13 West Colonnade, Euston Station, London NW1 (0171- 388 8353); Porter Nash Pharmacy, British Airways, 156 Regent Street, London W1 (0171-434 4700).