Most persons who acquire viral, bacterial, or parasitic infections abroad become ill within 6 weeks after returning from international travel. However, some diseases may not manifest themselves immediately, e.g. malaria may not cause symptoms for as long as 6 months to a year after the travelers returns to the UK.

Routine medical examination is not required after a short trip with no problems, or if the travelers has only suffered a trivial ailment. An examination may be advisable after an extended stay or if fever, diarrhea, vomiting, jaundice, urinary disorders, or skin or genital infections occur in the weeks following return from travel. During an evaluation of illness after travel abroad it is important to review your itinerary for all trips over the past 12 months. This may provide important clues as to the possible illness, especially since it may be something encountered infrequently in the UK