Dengue fever in American military personnel in the Philippines: clinical observations on hospitalized patients during a 1984 epidemic.

From June - August, 1984, 24 American military personnel were hospitalized with dengue (DEN) at Clark Air Base in the Philippines. Their infections were confirmed by serology using the hemagglutination-inhibition test and/or by virus isolation in Aedes pseudoscutellaris cell cultures. Most of the patients had a secondary type of antibody response probably reflecting prior vaccination against yellow fever. Three serotypes of DEN virus were isolated; 7 isolates of DEN 1, 4 isolates of DEN 3 and 3 isolates of DEN 2. All of the patients were Caucasian males between the ages of 20-43 years. All of the cases were clinically diagnosed as classical dengue fever. A platelet count of less than or equal to 100,000/microliters was a common finding (83.3%); however, hemoconcentration was not documented. Other major findings were the occurrence of mild hypotension (62.5%) and petechiae (37.5%). One patient presented with shock and upper gastrointestinal bleeding, but his diagnosis was complicated by a history of epigastric pain and use of aspirin. Although all of the patients fully recovered, the severity of illness was clearly documented by the average-length of hospitalization (5.9 days) and average time absent from work (8.7 days).