Modeling suggests gene editing combined with vaccination could eliminate a persistent disease in livestock

Abstract

Recent breakthroughs in gene-editing technologies that can render individual animals fully resistant to infections may offer unprecedented opportunities for controlling future epidemics in farm animals. Yet, their potential for reducing disease spread is poorly understood as the necessary theoretical framework for estimating epidemiological effects arising from gene-editing applications is currently lacking. Here, we develop semistochastic modeling approaches to investigate how the adoption of gene editing may affect infectious disease prevalence in farmed animal populations and the prospects and time scale for disease elimination. We apply our models to the porcine reproductive and respiratory syndrome (PRRS), one of the most persistent global livestock diseases to date. Whereas extensive control efforts have shown limited success, recent production of gene-edited pigs that are fully resistant to the PRRS virus have raised expectations for eliminating this deadly disease. Our models predict that disease elimination on a national scale would be difficult to achieve if gene editing was used as the only disease control. However, from a purely epidemiological perspective, disease elimination may be achievable within 3 to 6 y, if gene editing were complemented with widespread and sufficiently effective vaccination. Besides strategic distribution of genetically resistant animals, several other key determinants underpinning the epidemiological impact of gene editing were identified.

Applying genetic technologies to combat infectious diseases in aquaculture

“…A recent modelling study revealed that gene editing, when effectively combined with other disease control strategies, such as vaccination, may be able to eliminate persistent livestock diseases that are currently difficult to control. 676 However, according to this study, such desirable outcomes can only be achieved if the distribution of genetically resistant individuals into commercial populations is coordinated by breeding companies or national schemes.…”

Assisted Reproductive Technologies (ART) and genome editing to support a sustainable livestock

“…This achievement has received financial support from Genus plc (PIC, 2021), an international leader in the porcine and bovine genetics industry with worldwide presence. Based in the use of this tool it is possible to eliminate this persistent disease in few years without sacrificing animals (Petersen et al, 2022), a strategy never implemented before in any other eradication program.…”

Can breeders prevent pathogen adaptation when selecting for increased resistance to infectious diseases?

“…All strategies described above are also relevant to gene-edited resistance, including the use of other interventions to assist in decreasing the reproduction ratio to a value below 1 [ 68 ]. Resistance to the porcine reproductive and respiratory syndrome virus is a clear example where gene-editing might be an interesting strategy for infection control [ 68 ], although it is questionable whether many more of such cases exist.…”