Reduce relative disease risk by more than 75%

By Tim Nelson, CIO

Strong biosecurity goes beyond what individual producers can do at the farm level. With the increasingly integrated nature of production, it’s also about what all actors within a system need to do to reduce disease risk. When “Next Generation” biosecurity is practiced which factors in multiple routes of transmission, relative disease risk can be reduced by more than 75%.

In their 2019 paper Merrill et al1 conclude that their findings “challenge the assertion that simply increasing the communication of information regarding biosecurity strategy and implementation in the industry will result in increased investment in biosecurity.” Professionals who have worked with farmers for any length of time and understand the complexity of the drivers of behavioural change would not be surprised by this conclusion.

One only need look at the epidemiological reports from the recent UK Avian Influenza outbreaks to understand that despite years of plugging away at biosecurity messaging, things are not as they should be at the farm level.

But it’s not only on farm change that can make a big difference in keeping disease away from your livestock. Bring the research forward to 5 January 2024 in the Journal of the American Veterinary Association, where Dee et al2 report work undertaken over two years on 381,404 sows across 76 breeding herds.

They coin a phrase – “Next Generation Biosecurity (NGB)” and created this elegant diagram to demonstrate what they mean. They demonstrate that good biosecurity is not just about what producers can do at the individual farm level but about what all actors within a system need to do to reduce disease incidence (in this case porcine reproductive and respiratory syndrome, or PRRS).

From direct routes (pigs and semen) and indirect routes (mechanical, fomite-based) to aerosol and feed biosecurity, next-generation biosecurity layers prevention protocols together and applies it under the watchful eyes of trained inspectors and auditors. In their study the “PRRS incidence risk in NGB COMPLETE herds was 8.9% as compared to 40.0% in NGB IN¬COMPLETE herds”. In other words, where biosecurity measures were layered and with the multiple routes of potential disease transmission factored in, there was a 31% difference in risk between the herds. This is equivalent to a relative PRRS reduction risk of 77.7%.3


The connected nature of these systems creates opportunities to use technology to monitor and control movements and therefore prevent pathogen spread far more effectively.


The consolidation of production and services within large systems has created a burgeoning increase in the volume of physical (mechanical) connections between properties, including by people and vehicles. Property to property connections generally used to be localized and randomized, with different service providers and therefore different vehicles and people visiting farms. This is no longer the case. Even in geographically small countries the consolidation of production sites that receive services from just a handful of companies means farms are exposed to a much higher risk of cross contamination than in the past.

This brings with it significant challenges, but the connected nature of these systems also creates opportunities to use technology to monitor and control movements and therefore prevent pathogen spread far more effectively than in the highly randomized networks of the past.

Farm Health Guardian technology puts the concept of Next Generation Biosecurity into action. Visit to learn more.


1 Merrill SC, Koliba CJ, Moegenburg SM, Zia A, Parker J, Sellnow T, et al. (2019) Decisionmaking in livestock biosecurity practices amidst environmental and social uncertainty: Evidence from an experimental game. PLoS ONE 14(4): e0214500.
2 Improvements in swine herd biosecurity reduce the incidence risk of porcine reproductive and respiratory syndrome virus in breeding herds in the Midwestern United States 2024, Scott Dee, DVM, PhD, DACVM, Lisa Brands, Joel Nerem DVM, Adam Schelkopf DVM, Gordon Spronk DVM, Mariana Kikuti DVM, PhD, Cesar Corzo DVM, PhD, and Karyn Havas DVM, PhD, DACVPM.
3 Relative reduction = (Initial risk – Final risk) / Initial risk * 100%. So in this case: Initial risk = 40% Final risk = 8.9%. Relative reduction = (40% – 8.9%) / 40% * 100% = (31%) / 40% * 100% = 0.777 * 100% = 77.7%