Development of an Anti-Zika and Anti-Dengue IgM ELISA Assay: Evaluation of Cross Reactivity and Validation

Zika and dengue viruses (ZIKV and DENV) have been considered major global threats to humans in the past decade. The two infections display similar epidemiological and clinical manifestations. They are transmitted by the same primary vector, accounting for the co-circulation of the two viruses in regions where they are endemic. Highly specific and sensitive serological assays that are able to detect ZIKV and DENV antibodies (Abs) during the acute and convalescent phases of infections would help to improve clinical management and disease control. We report the development and characterisation of two monoclonal Abs, the ZIKV 8-8-11 and the DENV 8G2-12-21, which recognise the Zika non-structural protein 1 (NS1) and the dengue virus type 2 envelope protein, respectively. Both mAbs were used to set up enzyme-linked immunosorbent assays (ELISAs) specific for the detection of anti-Zika immunoglobulin M (IgM) and anti-dengue IgM and whose performance was similar to commercially available kits. These kits, intended to be used with the CHORUS Instruments, are rapid and require ≤50 µL of human serum. These tests could represent an affordable and reliable option for the rapid diagnosis of both ZIKV and DENV infections in developing countries, where these flaviviruses are endemic.