Location: Foreign Arthropod Borne Animal Disease Research
Project Number: 3022-32000-024-013-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 1, 2022
End Date: Jul 31, 2025
Rift Valley fever virus (RVFV) is a zoonotic insect transmitted virus endemic to Africa and the Arabian Peninsula. Virus infection causes abortions and high mortality in newborn ruminants. Humans can become infected through handling infected animals and animal products. Severe infections can include ocular disease, meningoencephalitis, or hemorrhagic fever with an overall case fatality rate of <1%. The spread of RVFV is of particular concern because of its widely recognized potential for being used as a bioterrorism agent and/or being accidentally introduced into North America. Currently, regional veterinary biosafety level (BSL) -2 diagnostic laboratories lack user-safe, modern, validated diagnostic tests to detect RVFV. The development and evaluation of a robust set of lateral flow assays are needed for both animal and public health national programs. There is a need to make these assays available for international standardization and potential further test kit development (commercialization). There are two objectives: 1) Adapt the current Cooperator Antigen detections assay develop for mosquito sample to veterinary samples such as serum, meat juices and milk. 2) Develop a lateral flow assay for small and large ruminant IgM antibodies to Rift Valley fever virus.
The cooperator has developed a commercial kit for detection of West Nile virus antigens from mosquito samples and more relevant to this project a similar assay for RVFV antigens. The ARS Team and Cooperator will evaluate various sample preparations and buffer formulations to adapt and evaluate the assay to veterinary samples such as serum, meat juices and milk. Recombinantly produce RVFV envelope protein (Gn) and nucleocapsid protein (N) are available and will be produced in large scale for assay development. The cooperator has previously developed the prototype IgG lateral flow (LTF) assays in collaboration with another ARS cooperator that were used by ARS to generate “proof-of-concept” for these devices. Similar design will be used to develop an LTF assay specific for IgM antibodies to RVFV for use with ruminant sera. These assays will be provided to ARS who will perform laboratory and field evaluation studies.