|PACHECO, JUAN - Us Deparment Of Homeland Security
|STENFELDT, CAROLINA - Oak Ridge Institute For Science And Education (ORISE)
Submitted to: Journal of Comparative Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/25/2016
Publication Date: 11/1/2016
Citation: Pacheco, J., Stenfeldt, C., Rodriguez, L.L., Arzt, J. 2016. Infection dynamics of foot-and-mouth disease virus in cattle following intra-nasopharyngeal inoculation or contact exposure. Journal of Comparative Pathology. 155(4):314-325. doi: 10.1016/j.jcpa.2016.08.005.
Interpretive Summary: Foot-and-mouth disease (FMD) is one of the greatest threats to livestock in the United States, yet much of its basic biology is unknown. Several experimental systems are available to study FMD in naturally infected species such as cattle. However, some systems are not good simulations of natural disease conditions, whereas others are not consistent enough to be useful systems to develop new vaccines. In this study, the authors developed a novel system for infecting cattle with FMD virus (FMDV) which is both consistent and very similar to natural conditions. The new system, called intra-nasopharyngeal (INP), was compared to 3 other systems for infecting cattle, each with 3 different virus strains. The overall conclusion is that INP is a safe and effective system for study of FMD in cattle.
Technical Abstract: For the purpose of developing an improved experimental model for studies of foot-and-mouth disease virus (FMDV) infection in cattle, three different experimental systems based on natural or simulated-natural virus exposure were compared under standardized experimental conditions. Antemortem infection dynamics were characterized in cattle exposed to FMDV through a novel, simulated-natural intra-nasopharyngeal (INP) inoculation system or through standardized and controlled systems of between- or within-species direct contact exposure (pig-to-cattle or cattle-to-cattle). All three systems were efficient in causing synchronous, generalized foot-and-mouth disease in cattle exposed to one of three different strains of FMDV representing serotypes O, A and Asia1. There was more variation in the timing of clinical infection following natural and simulated-natural virus exposure systems when compared to the conventionally used system of needle inoculation (intraepithelial lingual inoculation). However, the three optimized exposure systems described herein have the advantage of closely simulating field conditions by utilizing natural routes of primary infection, thereby facilitating engagement of mucosal host-defense mechanisms. Overall it is concluded that INP inoculation and standardized systems of direct contact exposure provide effective alternatives to conventional (needle) inoculation systems for studies in which it is desirable to simulate the natural biology of FMDV.