When you go on vacation, especially to exotic countries where the lifestyle is very different from what we are used to, you can quite often be confronted with diseases that do not occur with us. That risk grows as destinations become more exotic. Researchers at the University of Zurich (UZH), together with the World Health Organization (WHO), have developed an app that tracks data on these so-called travel illnesses.
The app, Illness Tracking in Travelers (ITIT), shows travelers which diseases are most common in which countries. Handy when traveling. However, the app can also help track outbreaks and the spread of infectious diseases such as dengue or new influenza viruses. “Travelers are an excellent reflection of what is happening globally. They also often play a role in introducing pathogens to different regions of the world,” says research leader Patricia Schlagenhauf of UZH's Epidemiology, Biostatistics and Prevention Institute. As an example, she cites the recent case of mpox in Sweden, which was imported by a traveler returning from Africa.
Tracking the spread of infections
The app allows people traveling to report any symptoms by filling out a short, user-friendly questionnaire. This information is then linked to location data and information on climate and air quality.
The research team has now analyzed data collected through the app between April 2022 and July 2023. The analysis involved 470 trips recorded by 609 people on all continents. It also showed that travelers became sick surprisingly often during their trips. More than a third of all trips involved health problems. The app is free to download and install via both the Google Play Store (Android) and the Apple App Store (iOS).
Mainly gastrointestinal problems
The most common health problems were gastrointestinal complaints. These occurred in nearly two in five (19%) of trips. Travelers to Asia suffered most frequently. In contrast, these symptoms were less common among those who traveled to Africa.
Significantly more women than men reported symptoms of diarrhea. It is possible that women are more susceptible to diarrhea, or that they were more conscientious in recording symptom information in the app. In contrast, respiratory illnesses (17%) such as colds were most common among travelers in Europe. Patricia Schlagenhauf recommends that travelers pack medications for diarrhea, nausea, headaches and fever, as these are the health problems that most limit people when traveling, according to the study.
Healthy and safe travel
The research team now wants to invite even more people to use the app. Larger data sets would allow the researchers to perform automated analysis using artificial intelligence, which could be used, for example, to detect dengue or mpox outbreaks at an early stage.
“This real-time bottom-up approach is much faster than top-down reporting systems. Mobile technologies offer a revolutionary solution to the way we track travel-related diseases. This will ultimately make our trips safer and healthier,” Schlagenhauf said. The findings of the app-based research were published in BMJ Open.
In the Netherlands several years ago, the Vakantiedokter app was developed by health insurer Zilveren Kruis. There, vacationers could ask questions about health complaints such as skin rashes, insect bites and diarrhea. The app was expanded at the time of the corona pandemic to provide remote care. Earlier this year, health insurer CZ launched the “Spoedzorg op Reis” app. Users of that app can communicate with medical professionals in real-time via live chat.
