Travis Beddoe, PhD, and doctoral student Alexandra Knox of the Department of Animal, Plant, and Soil Sciences and Centre for AgriBioscience at La Trobe University in Bundoora, Victoria, Australia, reviewed scientific studies from researchers worldwide who are using isothermic technology to detect pathogens (disease-causing organisms) that affect horses. They found promising results for a variety of viruses.

The Need For Early Detection

Protecting horses from infectious diseases requires knowing which horses are likely to spread harmful germs, said Knox. But identifying carriers usually requires expensive equipment and highly trained staff for sampling, as well as laboratory testing that involves delicate, controlled heating procedures to amplify DNA in the samples.

Additionally, depending on the test and the disease, results from standard in-lab procedures can take hours to weeks, with horses either quarantined during that time or actively spreading pathogens to other horses, said Beddoe.

Isothermic methodology, however, gives way to tests that don’t require specialized heating but use other techniques to amplify a sample’s DNA. As a result, scientists can create tests for a variety of equine disease pathogens using processes such as loop-mediated isothermal amplification (LAMP) and insulated isothermal polymerase chain reaction (iiPCR), he said.

With the advent of inexpensive isothermic technology test kits designed for in-barn use, caretakers could identify and quarantine sick horses and healthy carriers in record time, thereby minimizing disease spread, said Knox.

“Isothermal methodology is simple, rapid, and (capable of) providing real-time answers,” she said.

Promising Worldwide Results With Isothermic Technology for Horses

In their review, Beddoe and Knox found researchers have successfully used iiPCR, LAMP, and reverse transcription LAMP (RT-LAMP) to detect infection in horses or their vectors in field settings for multiple diseases, including African horse sickness (AHS), two kinds of equine influenza (H3N8 and H7N7), equine coronavirus, St. Louis encephalitis, Western equine encephalitis (WEE), West Nile virus (WNV), equine viral arteritis (EVA), equine herpesvirus-3 (EHV-3), equine herpesvirus myeloencephalopathy (EHM), and equine infectious anemia (EIA). Researchers have also run successful in-lab isothermic testing—with potential for field testing—for equine herpesviruses-1 and -4 (EHV-1 and EHV-4) and Hendra virus.

“Isothermal technology methods have been proven to be reliable for in-field use by nontrained personal and can tolerate sample variations (such as impurities and a range of sample types), whilst limiting costs,” Beddoe said.

Quick and Easy Field Tests Could Close Gaps in Biosecurity

The new technology could potentially lead to significant equine biosecurity improvements, helping better protect the approximately 59 million domestic horses worldwide in an industry valued at an estimated annual $300 billion USD employing 1.6 million full-time employees.

“In consideration of these advantages, isothermal technology is ideal for biosecurity and can be implemented in a range of environments, including resource-poor communities, allowing for strong biosecurity to be implemented worldwide,” he said.

Equine viruses regularly slip through biosecurity holes—a problem that could be resolved with faster and simplified testing, said Knox.

“While biosecurity is relatively sound in some countries, unfortunately due to variations in techniques and their application, as well as funding, many places are left vulnerable,” she said. “But even in areas with high biosecurity measures, such as Australia, disease outbreaks continue to occur. Sound biosecurity should be accessible worldwide to avoid these epidemics, and that requires cheaper alternatives to diagnostics and surveillance.”

Isothermic technology could help stop viral disease outbreaks in their earliest stages, and it could be the exciting future for equine biosecurity, Beddoe and Knox said.

“Isothermal technology is already paving its way to replace more traditional means of diagnostics and biosecurity,” Beddoe said.

Their paper, “Isothermal Nucleic Acid Amplification Technologies for the Detection of Equine Viral Pathogens,” was published by Animals on July 20, 2021.