Development of rapid, sensitive one-tube duplex RT-PCR assay for specific and differential diagnosis of Chikungunya and dengue.

Chikungunya and dengue, two arboviral infections are common in South-East Asia and their early clinical manifestations are very similar hence it is important to discriminate between them as early as possible for better clinical management. The aim of this study was to design a rapid, sensitive and specific method for the differential diagnosis of these two viruses simultaneously. A rapid one-tube duplex RT-PCR assay was developed that requires 110 min including RNA extraction, RT-PCR and agarose gel electrophoresis by using a novel Taq polymerase with high processivity. This one-tube duplex RT-PCR system with primers designed from the conserved regions of the genome allowed discrimination between the two viral groups. Bioinformatics analysis of the DNA sequences from PCR amplified products confirmed that this method was very specific and accurate. The time required for this duplex RT-PCR was comparable to the standard IgM capture ELISA method. This novel approach would help to diagnose specifically and accurately these two closely related arboviruses and enable early detection from blood. This method could be applied in resource limited settings, for surveillance in endemic regions or for routine epidemiological screening.