Disease lurks as an invisible threat to swine production across the world, but researchers at the University of Minnesota (UMN) College of Veterinary Medicine (CVM) are developing a novel tool to detect disease early using data from pig farms.  

This tool is based on using enhanced passive surveillance (EPS), a surveillance approach which incorporates standardized systems and targeted activities to help farmers and producers recognize disease events and make reports to veterinary authorities when necessary. 

The protocol being developed at the CVM is designed to take data already collected by swine producers and use it to alert them when additional investigation and diagnostic testing are warranted. A CVM research team is currently testing the surveillance tool’s effectiveness in detecting African swine fever (ASF) in regions where outbreaks are ongoing. Among them is Dr. Rachel Schambow, a PhD student working for the UMN Center for Animal Health and Food Safety (CAHFS). She is advised by Dr. Andres Perez, CAHFS director and CVM Endowed Chair of Global Animal Health and Food Safety. 

“ASF has no treatment or vaccine that’s widely available or commercially approved,” Schambow says. “We don't really have any physical tools to fight against it, so we rely on activities like surveillance to find the disease and then prevent it from spreading.”

ASF is a highly contagious viral disease affecting domestic and wild pigs—with a mortality rate nearing 100 percent—that has had far-reaching impacts globally. Since 2007, approximately 25 percent of the world’s domestic pig population has died due to ASF, Perez says. And that impact isn’t only felt by large swine producers. It represents a loss of income for families whose livelihoods depend on raising pigs and an increase in pork prices in areas where access to protein is limited. 

The disease has yet to reach the United States, but if it did, studies predict the impact on the swine industry would be disastrous—potentially as much as $50 billion over the course of 10 years. 

Gathering insight

Detecting the presence of ASF and other foreign swine diseases early and preventing the possibility of outbreaks is imperative for the USDA. The agency’s Center for Epidemiology and Animal Health is funding CAHFS’s surveillance development project through a cooperative agreement.

Building an effective surveillance tool requires understanding what types of data swine producers are collecting on farms and using deviations in that data to trigger alerts. 

As part of building that knowledge, Schambow has reached out to swine producers and information technology companies that design software used for managing production. These software platforms capture health information, such as an animal’s weight, breeding history, medical records, and more. 

Researchers are interested in the data that could be indicators of disease, such as clinical signs of illness and necropsy findings. An algorithm assigns values to these data points and that generates a weekly score. If a score reaches a certain threshold, a disease alert would be triggered and action would be taken to determine if disease is present on the farm. 

Each software is different, so researchers have employed several tactics to better understand their capabilities, including reaching out to producers with a voluntary survey asking them to list the types of data they collect and meeting with representatives from IT companies. 

“I'm not sure that people have really brought the IT companies to the table,” says Schambow, who has met with several companies to see demonstrations of their software platforms. “A lot of them are extremely enthusiastic about the idea of disease surveillance because they see it as another service they can offer that helps our farmers.” 

Next steps

As the research project progresses, data collection through outreach will continue to play an important role. 

“We’re really trying to reach a wide audience because we really need everybody's feedback to be able to create a solution that works,” Schambow says.  

Schambow, Perez, and other CVM Swine Program members hosted a workshop and focus group at the 2022 Allen D. Leman Swine Conference to bring together public and private stakeholders to talk about opportunities and obstacles for the long-term implementation of disease surveillance and how they can collaborate and combine efforts. 

Attendees represented a breadth of swine stakeholders that included research/academia, private swine software companies, USDA and other government agencies, primary swine veterinary clinics, and private swine farms and companies.

The push for collaboration in disease surveillance comes at a critical time as ASF continues to spread globally. In recent years, it has decimated swine herds in several Asian countries all while creeping closer to the United States.

“ASF has reached the Americas for the first time in 40 years, affecting the Dominican Republic and Haiti,” Perez says. 

The last time ASF infections were identified in the Western Hemisphere was in 1984, according to the World Organisation for Animal Health (OIE). Developing effective surveillance is vital for preventing the disease from reaching U.S. swine herds and causing widespread outbreaks.

“We are planning to pilot our EPS protocol on U.S. farms and continue developing it with the ideas gathered at the conference and through our survey,” Schambow says. “These results will also inform national-level discussions on ASF surveillance and promote the development of strategies in collaboration between public and private stakeholders, ultimately to create solutions that will benefit everyone and help in ASF prevention and control for the U.S.”