|Ferman Ii, Geoffrey|
Submitted to: Vaccine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/22/2005
Publication Date: 8/1/2005
Citation: Golde, W.T., Pacheco-Tobin, J., Duque, H., Doel, T., Penfold, B., Ferman Ii, G.S., Gregg, D.A., Rodriguez, L.L. 2005. Vaccination against foot-and-mouth disease virus confers complete clinical protection in 7 days and partial protection in 4 days:use in emergency outbreak response. Vaccine 23 (2005) 5775-5782.
Interpretive Summary: The most devastating aspect of an outbreak of foot-and-mouth disease (FMD) among livestock is the rapid spread of the virus and the resulting slaughter of all exposed animals. In the outbreaks in Europe in 2001, it was shown that vaccination could stem the spread of the virus. In this article, we show a careful, controlled analysis of the role vaccination could play in the response to an outbreak of FMD in cattle. Animals vaccinated 7 days before challenge were completely protected from clinical disease. In addition, animals vaccinated 4 days before challenge showed clear reduction in clinical symptoms and presence of the virus. Finally, vaccinated and protected animals were not able to spread the infection to new, unvaccinated animals. These results provide statistically significant data to policy makers in the process of deciding whether vaccination should be part of the response to an outbreak of FMD.
Technical Abstract: Recent outbreaks of foot-and-mouth disease virus (FMDV) demonstrate this highly contagious viral infection of cloven hoofed animals continues to be a significant economic problem worldwide. Debate about the most effective way to respond to FMD outbreaks in disease-free countries continues to center on the use of vaccines. In this report, we present data showing that presently available, commercial vaccine formulations can protect cattle against direct FMDV challenge in as little as 7 days. Four days after vaccination, animals had reduced disease severity and significant reduction in virus isolated from blood or nasopharengeal secretions. Further, 28 days post challenge, 7-day vaccinated animals did not transmit infection to naïve animals housed together for two weeks despite recovery of FMDV from their oesophageal-pharyngeal fluid. These results were consistent between two separate trials. These findings clearly indicate that outbreak response practices should be focused on rapid identification of the FMDV strain causing the outbreak and deployment of the appropriate vaccine for ring vaccination in the effected region.