Molecular and serological techniques to detect co-circulation of DENV, ZIKV and CHIKV in suspected dengue-like syndrome patients.

BACKGROUND: Arboviruses are important emerging viruses worldwide. The signs and symptoms of Zika virus (ZIKV) infection are similar to those presented by infections with dengue virus (DENV) and chikungunya virus (CHIKV). Furthermore, diagnosis of ZIKV infection is particularly challenging in dengue endemic regions and with co-circulation of DENV, CHIKV, and ZIKV, making diagnosis based solely on clinical and epidemiological data unreliable. As these three viral infections share similar clinical manifestations, differential diagnosis is crucial.

OBJECTIVES: In this study, diagnoses of ZIKV, CHIKV and DENV infections were investigated in 30 patients with suspected dengue fever residing in the area of co-circulation of these three arboviruses.

STUDY DESIGN: The study included whole blood and/or serum samples obtained from 30 patients with suspected dengue fever. All patients were tested for DENV infection as well as for CHIKV and ZIKV infections. Assays for detecting anti-DENV IgM and DENV RNA by semi-nested RT-PCR and ZIKV and CHIKV RNA by real-time RT-PCR were performed.

RESULTS: DENV RNA was not detectable in any of the clinical samples, whereas ZIKV RNA was detectable in 17 samples (56.7%). Co-infection by ZIKV and CHIKV was documented in one case. Of the 17 ZIKV-positive individuals, 8 showed reactivity for anti-DENV IgM, which suggested recent DENV infection, cross-reactivity or co-infection.

CONCLUSION: Our findings confirm that accurate laboratory testing is of paramount importance for differential diagnosis in areas of simultaneous transmission of different arboviruses with similar clinical presentations.