Epizootic Hemorrhagic Disease (EHD), a vector-borne disease affecting both wild and domestic ruminants, is transmitted by biting midges of the genus Culicoides. China's rapidly expanding livestock industry, the lack of field-deployable diagnostic tools for EHDV poses limitations for early outbreak containment.
Against this backdrop, a team of researchers from China developed a rapid and visual test strip for EHDV RNA detection based on RT-ERA and CRISPR-Cas12a. They reported their results in the Journal of Integrative Agriculture.
"Our approach is designed to achieve high sensitivity and specificity in detecting EHDV within ruminant populations, making it suitable for POCT in field settings," shares corresponding author, Yinglin Qi, a professor at Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences.
Conventional methods for EHDV detection and typing involve virus isolation in embryonated chicken eggs or cell cultures, along with ELISA or virus neutralization tests (the "gold standard" recommended by WOAH). The new system demonstrates three key advantages over existing methods:
- detection limit (1.7×101 copies/reaction) comparable to real-time RT-PCR but without requiring expensive thermocyclers;
- serotype-agnostic recognition of eight major EHDV strains, overcoming antisera dependency;
(3) compatibility with crude samples via HUDSON pretreatment, enabling on-farm use.
"With a turnaround time of <1 h and visual readouts, this platform enables on-farm decision-making for rapid containment of suspected EHDV outbreaks, significantly reducing reliance on centralized laboratories," says Qi.
"With further optimization for multiplexed serotyping and field ruggedness, this technology could serve as a model for decentralized diagnostics of other vector-borne livestock pathogens, ultimately strengthening global One Health initiatives," adds co-corresponding author Caixia Gao.
