Concurrent infections of dengue virus serotypes in Bali, Indonesia

OBJECTIVE: To describe cases of dengue virus (DENV) concurrent infections in patients from both local and international traveler visiting Bali, Indonesia. RESULTS: During a hospital-based study, 260 patients (from 161 local and 99 international traveler patients) were recruited. Among them, 190 were positive by DENV RT-PCR in which eight patients (five local and three international travelers) detected as having concurrent infections by two different DENV serotypes. Among the eight patients, the common dengue symptoms diagnosed were fever, headache, and myalgia. Six cases (75%) were diagnosed with dengue fever (DF) while two cases (25%) manifested with bleeding and were diagnosed with dengue hemorrhagic fever (DHF) grade 1. The DENVs concurrent infections involved all four DENV serotypes known to be circulating in Bali. Although cases of DENV concurrent infections have been implicated with severe manifestation, we observed that most of concurrent infections cases in our study were of mild clinical manifestation, that may be related to the changing of DENV serotype predominance which is occurring in Bali, Indonesia.