Dengue fever among travelers.

PURPOSE: The present paper describes the epidemiology and clinical manifestations of dengue fever in a nonendemic population of travelers.

PATIENTS AND METHODS: Clinical manifestations, epidemiologic information, and laboratory findings are described for a series of 18 Israeli travelers who tested serologically positive for dengue.

RESULTS: All the patients in the series contracted the disease in Southeast Asia, mostly in Thailand; 30% had to be evacuated due to severe morbidity. The clinical symptoms in travelers somewhat differ from the classical description among endogenous populations. High fever, chills, extreme fatigue, and severe headaches were prevalent. Other symptoms considered to be typical of dengue fever, such as myalgia, arthralgia, rash, biphasic fever, were uncommon. Laboratory findings were marked leukopenia, usually accompanied by lymphopenia, thrombocytopenia, liver function impairment, and hyponatremia. Some hemorrhagic phenomena were manifest despite it being the first exposure, without mortality.

CONCLUSIONS: Dengue fever among the nonimmune has a somewhat different manifestation from that reported for the Southeast Asian population. Although it is a significant cause for morbidity and hospitalization, it is underestimated as a factor affecting traveler's health. More efforts should be expended in developing an effective vaccine.