The global spread of African swine fever virus (ASFv) in recent years poses a great risk to swine production in the U.S. and associated agricultural industries and communities. Given the recent spread of ASFv into the Western hemisphere, the associated risk is on the rise. This is a matter of significant concern. ASFv has changed decades-long planning paradigms for animal disease response, given its steady spread across the world. The world watched as African swine fever virus (ASFv) smoldered in the Caucasus and parts of northern and eastern Europe. Alarm bells rang when ASFv surfaced in China in 2018. It is now established in the Caribbean, closer to the U.S. than any time in recent history. So, what does this have to do with Raman spectroscopy?
The method
Raman spectroscopy is a biophysical method in which a laser emits light with a specific wavelength onto an inspected object or material. This process reveals increases or decreases in photon energy as a result of the vibrational modes within the system. It is a non-invasive technique that can be implemented with relatively small, hand-held spectrometers. With proper library preparation and chemometric calibration achieved through careful measurement and study, the raw information collected by a spectrometer can be quickly processed to identify materials and substances in the field. In the animal disease diagnostic world, rtPCR is a standard test type for many reference tests for high consequence animal diseases. Yet, PCR requires a fair amount of sample preparation and usually a laboratory facility. With the increase push for field-forward diagnostics, Raman spectroscopy may prove to be a very useful diagnostic tool for multiple animal disease testing cases.
Dmitry Kurouski and his laboratory team at Texas A&M found that Rama-based sensing of diseases can be performed based on the identification of changes in plant and animal biochemistry. Such changes can be detected by Raman spectroscopy. Advanced statistical methods enable the determination of spectral signatures of various diseases. These signatures, together with the statistical models, can be made commercially available. This dataset can be integrated into a commercially available hand-held sensor, which can be used directly on the farm. One sensor, supported by specific libraries for detection, has the potential to detect and differentiate multiple diseases or possibly indicate and stage the occurrence of a syndrome.
Supporting national preparedness
CBTS is working with DHS Science and Technology to support national preparedness for high consequence animal and agricultural disease. One way this is accomplished is through researching the application of Raman spectroscopy in cases of animal disease. This work is novel. Dr. Kurouski has previously used Raman spectroscopy for detecting and characterizing Borrelia burgdorferi, the agent causing Lyme disease in humans. This serves as a helpful starting point for further exploring Raman’s use in mammalian disease detection. This project aims to detect endemic viral diseases in swine. It involves analyzing raw blood and body fluid samples and enhancing specific detection by inoculating samples with gold nanoparticles. When given a specific target, using gold nanoparticles coated with specific binding molecules—whether antibodies or RNA—opens up new possibilities for a combination of speed, specificity, and sensitivity.
ASFv has been a game-changing disease, following the world’s renewed awareness of the devastation caused by transboundary animal diseases during the 2001 foot-and-mouth disease outbreak in the United Kingdom. Given the BSL-3 biocontainment levels necessary for working with ASFv and the restricted availability of viral samples in the United States, an endemic viral disease of swine will serve as informative model and surrogate for ASFv. CBTS is well-suited to steer this innovative research and diagnostic exploration, with practical and essential end goals for national disease preparedness.
