Project Number: 6040-32000-081-017-I
Project Type: Interagency Reimbursable Agreement
Start Date: Oct 1, 2021
End Date: Sep 30, 2025
In response to the outbreak of SARS-CoV-2 infection in mink herds, USDA Animal and Plant Health Inspection Service (APHIS), Veterinary Services (VS) (USDA-APHIS-VS) has proposed priorities for SARS-related mink research and is seeking an interagency agreement with ARS to conduct agreed-upon research as quickly as possible within ARS laboratories [Western Regional Research Center, Albany CA (WRRC); National Animal Disease Center, Ames, IA (NADC); The United States National Poultry Research Center, Athens, GA (USNPRC)]. This proposal is to respond to the priorities planned for phase 1 (2 years). The objectives are to 1) evaluate and develop rapid pen-side/point-of-care (POC) detection of SARS-CoV-2 on mink farms, 2) investigate the pathogenesis of SARS-CoV-2 infection in mink, 3) evaluate vaccine efficacy, 4) determine the duration of infectious viruses in biological materials, and 5) mitigate the transmission risk of SARS-CoV-2 contamination on mink pelts. By understanding the pathogenesis, offering pen-side detection devices for early pre-clinical detection of SARS-CoV-2 on farms, and providing effective control measures, surveillance strategies in vulnerable farms and animals can be implemented faster, safer, and reliably to reduce illnesses and potential economic loss.
ARS scientists in Albany, CA (WRRC) will utilize 1) monoclonal antibodies and 2) aptamers against SARS-CoV-2 to develop SARS-CoV-2 lateral flow (LF) POC tests for mink samples. The standard LF assay (LFA) kit includes a test strip housed in a two-part plastic cassette, a sampling tool, a liquid extraction buffer, a sample tube, and a liquid transfer pipette. To facilitate remote pen-side testing and reduce testing error, ARS scientists in Albany, CA, have engineered a disposable biosensor assembly for LFA that integrates and simplifies end-user applications. This design provides an easy-to-use pocket-sized device for single-step testing. Depending on test requirements, the modular design accommodates different test strips, buffers, and sampling tool combinations. The user adds a test sample to the pre-filled buffer tube and, with a mechanical twist, initiates the test to deliver the liquid sample to the test strip. ARS scientists in Athens, GA (USNPRC) will evaluate commercially available human POC LF tests with real-time reverse transcription (rRT-PCR) and evaluate tests developed by the Albany lab. ARS scientists in Ames, IA (NADC) will study the pathogenesis of SARS-CoV-2 infection in mink by determining 1) peak shedding via swabs/oral fluid/rectal swab/sampling waste, and 2) the onset and resolution of disease. They will study vaccine efficacy by utilizing mink that have been vaccinated in the field and transported to NADC for challenges. They will also study the duration of shedding of the infectious virus and/or duration of infectivity of virus shed in biological materials. This gap in knowledge prevents an organized and reasoned control strategy on the farm. ARS scientists in Athens, GA, will study the contamination of mink pelts by determining how long viable virus remains on pelts and determine what treatments can be used to assure the product is free of viable virus. ARS scientists in Athens, GA, will evaluate a model cell culture system to evaluate and predict which SARS-COV-2 variant viruses have an increased or decreased risk of infecting cells expressing the mink ACE2 protein.