Go anywhere remotely exotic, and the chances are you will return with more than your duty-frees - hepatitis, dengue fever, malaria and tick-borne encephalitis for starters. You are strongly advised to keep well clear of all creatures great and small - household pets might be rabid and the humble sandfly could be playing host to the dreaded leishmaniasis parasite.
Avoid salads, ice-cubes and ice-cream, and remember to peel any fruit before you eat it. Naturally, you will ensure that you remain permanently smothered in an odoriferous melange of sun cream and mosquito repellent. But even that won't be enough to deter the time-share sharks, pick-pockets, predatory tour reps, short-changing waiters, assorted lager louts and investigators from the Consumers' Association who want to know if you are enjoying your holiday yet.
Fortunately, there is somewhere you can visit without having to suffer any of this hassle. Forget the picture-postcard destinations your travel agent has on offer - spend your summer in cyberspace. It has never been easier to make the journey, as you will discover if you abandon Holiday Which? in favour of this month's issue of Which? itself. You will a find a guide to what's on offer on the Internet - a detailed comparison of what the most popular Internet service providers charge and a summary of the assorted added extras they offer. Which? is keen to plug its own service provider, but, with commendable honesty, strongly recommends two of its competitors - America Online ("easiest to install") and Virgin Net ("good value").
If you have never been on-line, this summer is the ideal time to find out what all the fuss is about. The universities are the heaviest users of the Internet, but they shut up shop during July and August.
It's also the season when even the most addicted geeks are sometimes tempted to park their hard discs, don their anoraks and venture out of doors - if only to confirm their suspicion that there is nothing in the whole wide world to compare with the wonders of the World Wide Web. So, although the Internet is still a frenzy of activity, you are less likely to be frustrated by the gridlock and hold-ups that regular users routinely endure.
If you are running Windows 95, you don't need to acquire any special software or worry about which of 250 service providers you should choose. If you are prepared to key in your credit card details, you are given automatic access to the Microsoft Network (MSN).
You would normally be charged for the service, but Microsoft offers a month's free trial. When the month is up, you simply cancel your account and contact one of the many other providers who are ready and willing to tempt you with a free introductory offer. So after trying MSN, you could work your way through Which? Online, Virgin, America Online, CompuServe and LineOne, which would enable you to enjoy the Internet until well into the new year without having to fork out a penny in charges.
Like any other holiday destination, cyberspace is no paradise. As the Which? survey points out, many users find much that leaves them feeling distinctly queasy. But to be forewarned is to be forearmed. And always remind yourself that nothing you encounter on the World Wide Web could possibly cause you as much harm as a sandfly playing host to the leishmaniasis parasite.