THERE were a few possible reasons for the severe, incapacitating stomach cramps that forced University of Wollongong PhD student Rachel Przeslawski into a doctor's office in London last year with complaints that "aliens" had invaded her stomach and caused two days of excruciating pain.

Was it drinking tap water in rural Malaysia? The chicken simmering away all day in big pots at the hawker stalls that she'd readily consumed? Swimming with elephants in a murky creek?

She's still not sure. The symptoms subsided after a few hellish days and allowed her to get on with her trip. Considering that Przeslawski hadn't consulted a doctor before travelling and was not vaccinated against hepatitis A or B or typhoid, things could have turned worse. Stupid, she concedes, but the fact is Przeslawski is far from unique.

Late last year a Newspoll survey on behalf of the pharmaceutical company Aventis Pasteur found nearly 60 per cent of travellers do not receive vaccinations for preventable diseases before they travelled to exotic destinations. Another study, by the Travel Health Advisory Group (THAG), found more than 50 per cent of the 500 Australian travellers surveyed did not seek any health advice before travelling.

"We do these surveys almost annually, and in the last six years the figures have remained constant," says Dr Bernie Hudson, microbiologist and infectious disease physician at the Royal North Shore Hospital in Sydney and chair of THAG. "People think they're not at risk, and they are, even if they are going to be in developed countries."

Think SARS, influenza, rabies. And while hepatitis A is most common in the developing world, western countries are not immune – Belgium had an outbreak of more than 200 cases in July and August.

When it comes to smart travel, Hudson says Swiss travellers lead the pack as the most proactive regarding their health. Australians rank about the same as North Americans, and UK travellers lag behind the lot.

Given that activities as simple as sipping a drink chilled with ice or brushing your teeth with water from a sink, as tempting as downing a meal from a street vendor or as seemingly innocuous (or unavoidable) as using a public restroom can put a traveller in contact with diseases like typhoid and hepatitis A, it's not surprising the Newspoll survey found 98 per cent of unvaccinated travellers had done at least one thing that would have put them at risk of contracting such diseases.

Almost 50 per cent of people experience some health problem during their travel to a developing country and about 8 per cent seek medical attention either while they're still travelling or once they arrive back, according to The Text Book of Travel Medicine and Health, published in 1999.

Diarrhoea is the most common health problem travellers to the developing world face, and it can be more than just a source of discomfort, especially in young children, because it can cause severe dehydration.

The vaccine-preventable disease you're most likely to pick up overseas is hepatitis A. Staff at the Matraville Travel Clinic Australia (part of the Matraville Medical Complex in Sydney's eastern suburbs) have seen their fair share of returned travellers with such cases. And it's not a pretty sight.

"You can be off work from anywhere from a few weeks to six months," says Dr Jerry Schwartz, the clinic's medical director.

Schwartz says the problems are amplified in young children and the elderly, and can even be fatal. The disease attacks the liver and can cause unsightly symptoms like jaundice, but just as disturbingly, some people contract the disease and show no symptoms at all. That means they may be spreading it without even realising it, which was probably the case for one elderly woman in her 80s who came into the practice and was diagnosed with the illness despite not having travelled overseas. She had been in contact with a young traveller and might have contracted it from him. It took several months – and a few frightening hospital visits – before the woman finally recovered.

Most travellers think it won't happen to them. Maybe they've been to the same spot several times and experienced no problems, or maybe they've had friends go and come back without any horror stories in tow.

"Everyone's banking on the fact that they're not going to have any problems that could have been prevented," says Dr Bob Kass, chief medical advisor of The Travel Doctor, a national travel advisory service.

So just how big is the risk?

"The risk for hepatitis A in less developed countries is between one in 50 and one in 300, depending on whether you're staying in a backpacker or a five-star hotel," Kass says.

"The longer you go, the less stars in your accommodation, the more rural you go and the more contact you have with local people, the more risk you have," Hudson says.

That said, one of the biggest misconceptions people hold is that staying in five-star accommodation negates health risks. It lowers the risk, but certainly doesn't make it disappear. So the fact that the THAG study found folk staying in luxury accommodation to be less likely to be vaccinated is somewhat disconcerting, doctors say.

"It's a false sense of security that you get," Kass says. He points to an experience of his own, a five-star trip to Phuket where he and his family stayed comfortably (and safely) at an international hotel..

"We went on a day trip on a boat and the kids were swimming around the coral when someone flushed the toilet . . ." You guessed it, there it went, right out into the sea where his children were playing.

One patient he saw contracted typhoid while staying at a luxury resort in Bali on a breezy five-day trip, most likely at one of the beachside happy hours where mussels and oysters and other worrisome goodies abound. Kass says that while he wouldn't have recommended the typhoid vaccine for such a low risk itinerary, he would have gone over the do's and don'ts of safe eating and drinking, so the two weeks the woman spent in the infectious disease unit in hospital could have been avoided.

Four or five-star hotels may not be as clean as one might expect, says Dr Peter Demaio, medical director at Travel Health Care in Burwood, Melbourne. Often the kitchen-hands are the lowest paid of all the staff, he says, so you might be in a place where the foyer is fantastic, but the food handlers might not be aware of proper hygiene standards.

``People believe that better quality hotels make them immune to these things, but unfortunately mosquitos don't care whether you're staying at the Taj Mahal or the local pub,'' Demaio says. ``People also think if you're careful you'll be fine, but mosquitos don't particularly differentiate between people who are very, very careful and those who aren't either.

There's an inherent risk when you travel, irrespective of where you're going or how careful you are.''

And when it comes to malaria, the potentially fatal mosquito-borne illness so common in Africa and Southeast Asia, that's especially true. The number of cases of malaria imported into Australia fluctuates between 600 to 1200 a year, Hudson says, with 25 to 33 per cent of the cases being of the potentially fatal strand. On average the number is usually between 700 to 900, according to Nicholas Zwar, a professor of general practice at the University of New South Wales. Papua New Guinea, the Solomon Islands, Vanuatu and Southeast Asia are the most common places Australians contract the disease, and the chances increase for travellers who stay overnight in rural areas, Zwar says.

Anti-malarial pills like doxycycline and chloroquine are some of the prevention methods most widely prescribed by doctors, but the tablets are not always popular, especially among budget travellers going away for long periods of time. The pills have a reputation for side effects and can be somewhat expensive and inconvenient since you've got to remember to take them every day.

They are between 90 and 93 per cent effective, so even if they are being taken according to the instructions, a person could still conceivably contract the illness. Not surprisingly, studies show that most people who contract malaria were either not taking any anti-malarial tablets at all, or not taking them correctly, meaning they skipped a day or two here or there, or stopped taking them too soon, Hudson says.

But there have been cases of people who did everything they were supposed to do and still contracted malaria. ``We as doctors can't assume that by giving someone a script for an anti-malarial medication that they will in fact get the prescription filled and take the medication as suggested,'' Kass says. Many people, after hearing the negatives from other people and reading scary tales on the internet, will not take anything, so it's essential they understand the importance of doing everything possible to avoid exposure to mosquitos altogether.

And it's equally important that they are aware of the symptoms of malaria in case they should become ill, he says. ``No one should ever die from malaria as long as they seek a diagnosis as soon as possible by having two or three blood slides over 48 hours _ not just one. Malaria is easily diagnosed, can be treated with the drugs available and you do not have it for life, that is an urban myth,'' Kass says.

The defining symptom of malaria is a violent fever, and often shivering, abdominal cramps, nausea and other symptoms that accompany fevers will be there as well. The fever might not last too long, an hour or two, Schwartz says, before it settles. But with malaria, unlike the flu, it will come back, usually in about 48 hours.

The key is getting to a doctor straightaway and making sure the doctor knows you've been away. Hudson says there have been cases where people have died within 24 hours of the first symptoms.

Other debilitating illnesses include dengue fever, yellow fever, cholera and Japanese encephalitis. So what can you do to reduce your chances of a bed-ridden stint?

Develop a plan and a schedule for your trip, for starters, Demaio says. Decide where you're going and for how long, because the vaccinations you'll need and the precautions you should take can vary considerably, even within the same country, he says. Allow plenty of time, but not too much either. Don't head to the doctor six months in advance because things can change considerably in that amount of time. Six weeks before you head off is ideal.

Many vaccinations take a few weeks before they have any effect.

It's also worth seeing a travel medicine specialist rather than just going to your GP. This can save time, as they're more likely to stock most of the vaccines you'll need so you won't have to fuss around going to the pharmacy and then coming back for a second appointment. It can save money as prices for injections vary by as much as 15 to 20 per cent and larger travel clinics may be able to buy in bulk and get cheaper prices.

Travel medicine specialists also attend conferences, subscribe to journals and databases, and generally have access to more comprehensive and current information about specific destinations.

Someone who specialises in travel medicine is also more likely to consider details a GP might not have thought of _ for instance, certain anti-malarial medications can cause disorienting side effects. Maybe not a big issue for the average traveller, but for the scuba diver? Not fun, Demaio says.

And don't forget the practical measures anyone can take: things like bringing along gastro-intestinal kits and first-aid kits, regularly applying mosquito repellant, wearing protective clothing and drinking bottled water, to name a few.

The good news is that the more you travel the less hassle you'll have to endure.

``A person who is well prepared and travels regularly may require very little in the way of injections because they're already up to date. Vaccinations against hepatitis A and B last a long time if you get the boosters and typhoid lasts three years. If they are going to a place where malaria is a problem that could be the only thing they need, or they may just need a flu shot depending on where they are going and the time of year,'' Hudson says.

But if trends continue the way they have in recent years, many travellers will continue to put themselves at risk.

Przeslawski, for one, says chances are she won't change her habits anytime soon.

``It's really not worth the cost time-wise or convenience wise if I'm just going on a short trip, in terms of the potential risk of getting some little bug that's probably going to clear up on its own anyway,'' she says.

www.tmvc.com.au

www.vaccinations.com.au

www.travelhealth.com.au

www.cdc.gov/travel/