Users of RDTs for dengue should be aware that many of these tests have a diagnostic accuracy that falls well below the manufacturers' claims. If an acute specimen yields a negative result, a convalescent serum sample should be tested to confirm the result. No RDT adequately differentiated primary and secondary dengue infections, and the tests should not be used for this purpose.

Replication of flaviviruses (family Flaviviridae) occurs in specialized virus-induced membrane structures (IMS). The cellular composition of these IMS varies for different flaviviruses implying different organelle origins for IMS biogenesis. The role of flavivirus non-structural (NS) proteins for the alteration of IMS remains controversial. In this report, we demonstrate that West Nile virus strain New York 99 (WNVNY99) remodels the endoplasmic reticulum (ER) membrane to generate specialized IMS. Within these structures, we observed an element of the cis-Golgi, viral double-stranded RNA, and viral-envelope, NS1, NS4A and NS4B proteins using confocal immunofluorescence microscopy. Biochemical analysis and microscopy revealed that NS4B lacking the 2K-signal peptide associates with the ER membrane where it initiates IMS formation in WNV-infected cells. Co-transfection studies indicated that NS4A and NS4B always remain co-localized in the IMS and are associated with the same membrane fractions, suggesting that these proteins function cooperatively in virus replication and may be an ideal target for antiviral drug discovery.

Therapies to prevent or reverse endothelial dysfunction and vascular leak found in dengue hemorrhagic fever (DHF) have not been identified. In this review we summarize dengue viruses and the spectrum of human disease and highlight evidence of endothelial cell dysfunction in DHF based on studies in patients and mouse and tissue culture models. Evidence suggests that both virus antigen and host immune response, can cause endothelial cell dysfunction and weaken endothelial barrier integrity. We suggest possible therapeutic interventions and highlight how therapies targeting altered endothelial function might be evaluated in animal models and in patients with DHF.