Changing epidemiology of dengue fever in travelers to Thailand.

A study was conducted to evaluate the incidence and seasonal pattern of dengue fever occurring among Israeli travelers to Southeast Asia. The illness was diagnosed by Israeli physicians stationed abroad and by serological methods carried out in Israel. Between 1994 and 1998 dengue fever was confirmed in 103 travelers, 80 of whom were diagnosed in Israel. A sharp increase in the incidence was noted in 1998 as compared with the previous 4 years. The attack rate during 1998 in a defined group of travelers was 3.4/1,000 and reached a peak of 5/1,000 during the dry season of 1998.