New study sets out to elevate asymptomatic COVID-19 surveillance practices

November 13, 2020

Researchers from the College of Veterinary Medicine and School of Public Health will investigate how detecting asymptomatic disease can reduce spread

ST. PAUL, MINN. --- University of Minnesota College of Veterinary Medicine (CVM) faculty are collaborating with researchers at the School of Public Health (SPH) to roll out a surveillance study of COVID-19 among asymptomatic populations. The study will compare the incidence of infection in individuals participating in asymptomatic COVID-19 surveillance to individuals with self-reported incidence of COVID-19 illness, while also investigating the performance and efficiency of a surveillance system that uses pooled testing instead of individual testing. 

“The CDC has estimated that 40-50 percent of individuals infected with the COVID-19 virus are asymptomatic infections and, without testing, these individuals are likely to play a major role in disease spread,” says Scott Wells, DVM, PhD, professor in the CVM’s Department of Veterinary Population Medicine (VPM), who is leading the study. “We expect that twice-weekly use of relatively low-cost pooled testing will identify these infected individuals, which will allow them to self-isolate and reduce the risk of spreading infection.” Wells has accumulated decades of experience using epidemiology to perform surveillance, prevention, and control measures on infectious disease in cattle and other food animal agriculture settings. 

Results from this study should help clarify when pooled sample testing should be used over individual sample testing. It will also help advance scientific understanding of the risks of disease transmission from infectious asymptomatic COVID-19 carriers. The University of Minnesota Genomics Laboratory will test pools of five samples and expects to turn results around within 24 hours. If a sample pool garners a positive result, the individuals whose samples were used in the pool will each be tested to identify the infected individual.

The study will rely on volunteers in the CVM community. Eligible participants include fourth year veterinary students, as well as the veterinary technicians, faculty, residents, graduate students, and interns who instruct these students in clinical rotations. Participants will be tested twice weekly for SARS-CoV-2 for 13 consecutive weeks. “This project becomes a real-life ‘teachable moment’ exercise through which the students can gain a personal understanding of these same tools and concepts we use in veterinary medicine — disease surveillance, test capabilities and limitations — all the elements they will use in practice.” says Jerry Torrison, DVM, PhD, DACVPM, director of the Minnesota Veterinary Diagnostic Laboratory (VDL). “Of course, the real-life part of helping keep our community safe is paramount.”

This project brings together experts in diagnostics at the VDL and the UMN Genomics Center, in epidemiology and disease modeling at the CVM, and in public health from the CVM Veterinary Public Health and Preventive Medicine Residency Program and the School of Public Health. “We are excited to be able to use our collective experiences and expertise to protect the health of our veterinary students and instructors at the CVM, and support the safe training of veterinary students during this pandemic,” Wells says. 

“This study is a prime example of how mathematical models of disease spread can guide surveillance,” says Kim VanderWaal, PhD, assistant professor in the VPM. Vanderwaal, whose position is funded in part by the Minnesota legislature’s Agricultural Research, Education and Extension Tech Transfer program, has extensive expertise integrating diverse and complex epidemiological data to better understand and predict pathogen spread within large agricultural production systems. “Our model of asymptomatic COVID transmission in workplace settings quantifies how much more important frequent testing is as cases surge in our county.”

Clinical rotations are a vital part of veterinary, nursing, dental, and medical education and the pandemic has made in-person clinical training increasingly difficult. The CVM has worked hard to ensure that students in their fourth year of the DVM program safely retain access to this clinical training. Information gleaned from this study could help other health professional programs across the country more safely navigate the uncharted waters of this global pandemic. 

Volunteer study participants will simply swab the inside of their nostrils and return their test to collection sites across the U of M campus twice a week for the study duration. Study investigators are also working to add additional test collection sites at the CVM’s additional training locations such as the New Sweden Dairy Facility and West Metro Equine Clinic. Test results from this study will be shared with the Minnesota Department of Health for contact tracing purposes to protect public health. 

This study is funded by the University of Minnesota Medical School’s Office for the Vice Dean of Research. In addition to Wells, Torrison, and Vanderwal, the team of CVM and SPH faculty includes Michael Mahero, DVM, PhD; Tim Goldsmith, DVM; Sandra Godden, DVM; Maxim Cheeran, MVSc, PhD; Scott Madill, DVcs, DACT; Perle Zhitnitsky, DVM, MSpVM; Jeff Bender, DVM, MS; and Craig Hedberg, PhD.

The study team is beginning recruitment now. If you are eligible and interested, contact Jan Mladonicky at [email protected].


Scott Wells — [email protected]