Development and evaluation of a new epitope-blocking ELISA for universal detection of antibodies to West Nile virus

Abstract

West Nile virus (WNV) is an emerging zoonotic pathogen with a wide range of hosts, including birds, horses and humans. The development and evaluation of the performance of a new enzyme-linked immunosorbent assay (ELISA) are described for rapid detection of WNV-specific antibodies in samples originating from an extensive range of vertebrates susceptible to WNV infection. The assay uses a monoclonal antibody (MAb) which binds whole virus particles and neutralizes infection in vitro by recognizing a neutralizing epitope within the envelope (E) glycoprotein of the virus. This MAb, labelled with horseradish peroxidase, was used to compete with WNV-specific serum antibodies for virus-binding in vitro. The epitope-blocking ELISA was optimized in a manner that enabled its validation with a number of experimental and field sera, from a wide range of wild bird species, and susceptible mammals. The new ELISA exhibited high specificity (79.5-96.5%) and sensitivity (100%), using the virus-neutralization test as reference standard. It also required a much lower volume of sample (10 μl per analysis) compared to other ELISAs available commercially. This new method may be helpful for diagnosis and disease surveillance, particularly when testing samples from small birds, which are available in limited amounts.

A Novel System for Rapid and Cost-Effective Production of Detection and Diagnostic Reagents of West Nile Virus in Plants

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Do Wild Ungulates Allow Improved Monitoring of Flavivirus Circulation in Spain?

“…A WNV blocking ELISA was used to screen for flavivirusspecific immunoglobulin G (IgG) antibodies (Ingenzim WN Compac Ò ; Ingenasa, Madrid, Spain) (Sotelo et al 2011). Following the manufacturer's instructions, samples with percent of inhibition > 40% were considered positive.…”

Rift Valley and West Nile Virus Antibodies in Camels, North Africa

“…RVFV antibodies were detected by using a competitive ELISA ( 4 ), and samples yielding positive ELISA results were confirmed by virus-neutralization test. WNV-specific antibodies were detected by ELISA ( 5 ), and positive results were confirmed by virus-neutralization test. AHSV-specific antibodies were detected by using the ELISA prescribed by the World Organisation for Animal Health.…”