More and more people worldwide are travelling – not just on holiday but also for study or work. This not only increases the risk of them becoming ill themselves, but also the risk of introducing new pathogens into the country of origin. This is a particular problem when it comes to antibiotic-resistant pathogens.
A dissertation from the medical travel clinic at Umea university in Sweden has now investigated how well travel clinics can reduce the risk of illness among travellers. They also investigated how good the advice is and what factors influence an individual’s risk – aspects that could contribute to improving travel health advice. In two studies, Martin Angelin and his colleagues surveyed 1.698 and 1.059 people who had visited the travel clinic for a consultation. Two-thirds of respondents surveyed after their trip said they had followed the medical advice.
Youngsters and men were at more risk
The risk for health problems abroad was highly dependent on individual factors. Thus it was found that younger travellers (under 31 years) followed the advice given at the consultation less closely and were at more risk during the trip. This included, among other things, unprotected intercourse. At the same time, young people were ill more often than travellers over 30. And they had an increased risk of being involved in traffic accidents.
There were clear differences even between women and men: women travelling to comparable destinations were vaccinated more often than men, particularly against Japanese Encephalitis. In addition, more people were vaccinated against hepatitis A when visiting a more distant destination (Thailand) than for a nearby destination (Turkey) – although the disease is spread equally in both countries and between 2004 and 2014 more people were infected with hepatitis A in Turkey than in Thailand.
“The results show that different groups have a different risk perception and a different willingness to take risks”, says Angelin. “Apparently men appreciate the risk of becoming ill on a trip less than women. And young people are willing to take more risks than older people. These aspects should be considered in travel medical advice”. So ways should be found to motivate risk-taking people to protect themselves from disease as much as possible. In addition, the importance of adequate immunisation even for closer travel destinations should be promoted.
Education and advice are useful – but there is room for improvement
A surprising result of Angelin’s studies: People following the travel health recommendations were ill just as often as someone who had failed to comply with the advice. The effect was present primarily due to a high rate of travel diarrhoea. The lack of difference could be due to factors that a traveller has no direct influence on says Angelin – such as poor hygiene in restaurants. “Nevertheless, we should examine the recent critical travel health recommendations to find out what advice is really relevant”, says the doctor.
That advice is quite helpful according to a recent, large-scale study. Here the advice was associated with lower incidence rates for malaria, acute hepatitis and HIV. However, it did not contribute to a significant reduction in travel diarrhoea.
Individual advisory service
Another of Angelin’s study target groups were students who go abroad during their studies. This group was compared to leisure travellers at an increased risk due to health problems and the study found: More than half became ill while abroad. At the same time the young people behaved in a particularly risky manner when away from home: One-third tended towards hazardous alcohol consumption and many gained a new sexual partner with one third having unprotected sexual intercourse. Students from the health sector were particularly happy to take risks – even though they had received more health-related information prior to departure. “Maybe having medical knowledge provides a false sense of security”, says Angelin.
How important – but also difficult – the best possible protection against travel diseases is was presented by a study from the travel medicine clinic at the University of Zurich. It was about travellers with special health risks, such as the elderly, pregnant and breastfeeding women and people with underlying medical conditions. The study shows these people visit very similar destinations and have similar travel styles to other travellers. So many pregnant women and nursing mothers travelled to in areas with malaria or yellow fever even though a vaccination or prophylaxis is problematic for them. “In such cases, the advice is a real challenge – as in very young and very old traveller”, the authors write.
Resistance in luggage
Another international travel problem concerns the entire population: The introduction of antibiotic-resistant bacteria. Overseas travel is an important risk factor for intestinal colonisation of antibiotic-resistant pathogens. This topic is addressed by Angelin in another substudy. Accordingly, a third of the medical students surveyed are carriers of antibiotic-resistant bacteria (so-called extended spectrum beta-lactamase-producing enterobacteria or ESBL-PE) when abroad. The risk depended on the country visited and whether anyone had been treated with antibiotics during the trip. Travellers spending time in India and Southeast Asia were at a particularly high risk. “The risks are often minimal for the support of antibiotic-resistant bacteria”, says Angelin. “But increasing antimicrobial resistance in the countries of return increases the risk of sensitive people falling ill due to such pathogens”. By contrast, working with patients abroad was not a risk factor for colonisation with ESBL-PE. From the results, the authors recommend avoiding unnecessary antibiotic treatment in a foreign country.
Adjusted Risk Communication
“In summary, our results show that current travel health recommendations should be fully and critically reviewed”, says Angelin. “As a result, travel clinics for leisure travellers and students could be improved”. For example, advice on increased alcohol consumption, unprotected sex abroad and the risk of traffic accidents should be given along with disease advice.
At the same time, it was important to capture the previous knowledge and attitudes of travellers to health risks, found a study lead by Karin Leder from Monash University in Melbourne. “Travel medicine advisors should learn how to communicate risks”, said the scientists. “They should also address the individual’s risk perception and risk tolerance of travellers to motivate them to reduce health risks as much as possible”.
It makes sense to offer written material such as numbers or graphs on disease risk. And for younger travellers, Angelin says it might be advantageous to convey the risks and the benefits of preventive measures in new ways such as discussion groups or through social media.