[Risk groups in travel to tropical countries within the frame of mass tourism].

More than 10,000 tourists returning from tropical countries have been asked about health problems during their stay abroad. Preliminary results from the first 5,550 questionnaires indicate that 74,8% had complaints of any kind concerning their health and 13,6% can be considered as having been ill. The frequency of complaints and illness in relation to different variables is shown and the possibility of definition of high risk groups is being discussed.