BACKGROUND: Travel health risks documented by questionnaire surveys obtained (e.g., during homebound flights) are incomplete since they miss most patients who need to be repatriated. METHODS: All patient claim files were reviewed from 1997 to 1998, of the largest Swiss travel insurance company. RESULTS: Among 242 claims, 69.4% were due to illness, 30.6% due to accidents; infections were the most frequent illnesses, the extremities were the most frequently traumatized part of the body. Although the illness-to-accident ratio was 1:5 in industrialized countries and the Caribbean, it exceeded 3:0 in some developing regions. Accident proneness was noted in the first week abroad. CONCLUSION: Even if no denominator data are available, this analysis offers an insight in travel health risks, allowing comparison of the occurrences of very different, serious, health problems abroad.