Acute retroviral syndrome mimics dengue in Singapore.

Dear Editor, Both dengue and acute human immunodefi ciency virus-1 (HIV-1) can cause a febrile illness associated with myalgias, rash and blood count abnormalities, as noted in a single case report.1 In Singapore, suspected cases of dengue are usually managed as outpatients without confi rmatory testing, so acute HIV-1 may be misdiagnosed.2 If routine confi rmatory testing for dengue-like illness was performed, as recommended by the World Health Organization (WHO), misdiagnosis could be avoided. However this is diffi cult to implement in countries where dengue is common and patients bear the cost of testing. The objective of this retrospective study is to estimate the contribution of acute HIV-1 to dengue-like febrile illnesses through a retrospective review of hospital admission data to identify cases of probable dengue that were in fact acute HIV-1.