When you call the Travel Clinic, expect a recorded voice to answer. To get straight through to make an appointment, simply answer 'Yes' to the first question: 'Do you want to make or change an appointment?' and a human will pick up the phone. If you want to know more about vaccinations and/or the country you're going to, answer 'No' and you will be directed to the relevant information. Do not let this system put you off, it is actually quite helpful. Despite the fact that the clinic processes between 30 and 40 people a day, it's possible to arrange an appointment within 24 hours.

I arrived expecting to find a busy clinic full of hippies and screaming children, and was surprised to find it small but quiet, with wicker chairs and a cocktail lounge decor of pastel blue. While a doctor can be bleeped and in the clinic fairly quickly from the main hospital, the clinic is staffed by nurses only. Helen Brisbane, who saw me, was friendly and able to advise me on my chequered inoculation history. Being born and raised in Trinidad and having spent four years in Papua New Guinea, I was unsure of what jabs I'd had in the past and had lost all the records anyway. She consulted her manuals and told me about the outbreaks of disease in the places I'd lived - and assessed what jabs I'd probably been given. I explained that I was about to fly to Ghana and again she knew what the situation was out there. Yellow fever - a huge outbreak which had now spread into neighbouring countries.

In all, I was to have five jabs. Hepatitis A (in my bottom), polio (in a sugar cube), and tetanus, typhoid and yellow fever (in my left arm). I felt no pain, though my rear did seize up for about a day after the hepatitis shot. Jabs are approximately pounds 8 each, though my yellow fever was pounds 14. Some are more expensive, like rabies (pounds 15) and hepatitis B (pounds 30).

The clinic also gives good advice on malaria and a consultation, which will also include information on related medical problems and allergies, costs pounds 15. If you then buy a vaccine and/or malaria medication, the consultation is free.

By the exit you can buy industrial strength sunblock and extremely potent jungle-formula insect repellents that you can spray on or dilute in water. Mosquito nets, HIV prevention kits (starting at pounds 7.99) and water purifiers are also on sale, as well as nifty-looking adventure kits.

My trip to the clinic was an eye-opener. I arrived thinking I had seen it all. I left with a clear understanding that Africa is in a league of its own for potentially fatal tropical diseases.

In all, I was in the clinic for about 30 minutes, though a visit need be only 10 minutes in some cases.

The Travel Clinic, The Hospital For Tropical Diseases, 4 St Pancras Way, NW1 OPE (071- 388 9600).

Appointments only or call their Healthline for information only on 0839 337733.