Maternal Zika virus (ZIKV) infection during pregnancy can have profound teratogenic effects including microcephaly and intracranial calcification. In adults, infection may cause acute inflammatory polyneuropathy. These complications appear after resolution of viremia. Thus, molecular assays of blood are typically insufficient to make the link between ZIKV infection and disease. An alternative approach to testing for ZIKV exposure is serology. However, specific serological implication of ZIKV can be confounded by cross-reactivity with closely related flaviviruses. We used high-density peptide arrays that tile the proteomes of a selection of arboviruses to search for ZIKV-specific linear epitopes that would enable the development of accurate serological tests. We identified a 20-amino-acid-long diagnostic peptide sequence in the NS2B protein of ZIKV that was immunoreactive with sera from patients with a confirmed history of infection with ZIKV but not other flaviviruses. We then established a ZIKV peptide ELISA (ZIKV-NS2B-concat ELISA) that enables sensitive and specific diagnosis of exposure to ZIKV.
Keywords: Arboviruses; Emerging infectious diseases; Flavivirus; Peptide ELISA; Serology; ZIKV-NS2B-concat ELISA; Zika virus.