Rift Valley Fever Viral RNA Detection byHybridization in Formalin-Fixed, Paraffin-Embedded Tissues.

Abstract

Sporadic outbreaks of Rift Valley fever virus (RVFV), a zoonotic, mosquito-borne, cause abortion storms and death in sheep and cattle resulting in catastrophic economic impacts in endemic regions of Africa. More recently, with changes in competent vector distribution, growing international trade, and its potential use for bioterrorism, RVFV has become a transboundary animal disease of significant concern. New and sensitive techniques that determine RVFV presence, while lessening the potential for environmental contamination and human risk, through the use of inactivated, noninfectious samples such as formalin-fixed, paraffin-embedded (FFPE) tissues are needed. FFPE tissuehybridization (ISH) enables the detection of nucleic acid sequences within the visual context of cellular and tissue morphology. Here, we present a chromogenic pan-RVFV ISH assay based on RNAscopetechnology, which is able to detect multiple RVFV strains in FFPE tissues, enabling visual correlation of RVFV RNA presence with histopathologic lesions.