[Imported fever. A diagnostic challenge].

Fevers without distinguishing symptoms in persons who have visited tropical or subtropical areas is an increasing health problem in most western countries. The condition may be caused by several different microbes, but among cases diagnosed in Norway five infections dominate: falciparum malaria, vivax malaria, typhoid fever, paratyphoid fever and dengue fever. Primary measures should be taken against immediate life-threatening diseases e.g. typhoid fever and falciparum malaria.