Diagnosis of dengue in Sri Lanka: improvements to the existing state of the art in the island.

Dengue fever (DF) is a mosquito borne virus infection which is endemic to the tropical regions of the world. In Sri Lanka, the first sero-positive case was reported in the 1960s; since then the island has experienced several outbreaks of DF/dengue haemorrhagic fever (DHF). The disease is more prevalent in some parts of the country where rapid urbanisation has taken place. Diagnosis of DF/DHF is mainly done using the clinical features only due to the unavailability of laboratory diagnosis in many parts of the country and this might lead to over or under diagnosis of the disease. A rational diagnostic approach which combines the history and clinical profiles together with specific virological laboratory data would help in the correct identification of the disease. Furthermore, a feasible algorithm for the laboratory diagnosis of dengue will help to confirm the cases with a high level of clinical suspicion. This would then facilitate the notification of correctly identified cases to the public health authorities to assess the dengue burden. The scope of this review is to improve the existing laboratory diagnosis of DF/DHF by proposing a feasible algorithm to implement in Sri Lanka that would enable better detection of cases.