Research Summary - 3
Model-based impacts of improved traceability of cattle in Foot and Mouth Disease outbreaks in the United States
| Date/Time: |
9/13/2025
08:15
|
| Author: |
Michael Sanderson |
| Clinic: |
Kansas State University College of Veterinary Medicine |
| City, State, ZIP: |
Manhattan, KS 66506 |
M. R. Smith, DVM
1
;
M. W. Sanderson, DVM, MS, DACVPM
1
;
1Center for Outcomes Research and Epidemiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, 66506
Introduction:
The implementation of electronic identification (EID) as a requirement for the identification of livestock in the United States (US) improves the accuracy and speed in which animal health officials can trace outbreaks of disease. The objective of this project was to assess the impacts of rapid and accurate traceability of cattle in a simulated Foot-and-Mouth Disease (FMD) outbreak in the United States. The targets for analysis were the number of premises that became infected, the duration of the outbreak, and the farms impacted by surveillance efforts.
Materials and methods:
The spatially-explicit disease transmission modelling program, InterSpread Plus (ISP) was used with a US national population file, animal movement parameters, and FMD-specific parameters to simulate outbreaks. Outbreaks were introduced in multiple regional locations (California, Nebraska, Texas, New Mexico, New York, and Tennessee) and farm types (dairy, feedlot, stocker, and cow-calf). Outbreaks were detected on day 8, 14, or 21 after introduction. The parameters for the current tracing ability were developed from tuberculosis and brucellosis tracing efforts and could take as many as 7-10 days to complete with an estimated 85% accuracy. The ideal EID tracing resulted in all traces completed within 24 hours with 99% accuracy.
Results:
The most notable changes in number of infected premises (outbreak size) were noticed with rapid detection of the index case of FMD. Outbreaks that were detected on day 8 were steadily smaller than those detected on day 14 or 21 regardless of the tracing level implemented. Across all detection days, moving from current to ideal tracing consistently decreased the likelihood for large outbreaks. In outbreaks detected on days 8 or 14, the impact of tracing was less remarkable for median and smaller outbreaks but did decrease the 90th percentile. The impact on the 75th percentile was highly regionally variable in day 8 and 14 detection scenarios. In outbreaks detected on day 21, the impact of tracing was more pronounced, decreasing the 75th and 95th percentiles dramatically. In especially large outbreaks, the utilization of ideal tracing decreased the median value for number of infected premises. Similar trends were seen in the duration of outbreaks and number of farms impacted by the surveillance efforts.
Significance:
The results of our model supports the need for continued education of veterinarians and producers to make the first diagnosis of FMD as quickly as possible. It also supports the need for improved traceability of cattle that is rapid and accurate to decrease the potential for large outbreaks in the event of an FMD introduction in the United States. In smaller outbreaks, tracing had less potential to be impactful. However, in larger outbreaks tracing dramatically decreased the risk of large outbreaks. An improved traceability system could also decrease demands for human labor to conduct traces and surveillance during the outbreak. Lastly, improved traceability could improve business continuity of producers during and outbreak through decreased restriction of farms needed for surveillance. More research into the economic trade-offs and EID feasibility are needed to determine the best implementation strategy of EID tracing systems.
