Foot-and-mouth disease (FMD) is a contagious picornavirus infection that mainly affects cloven-hooved mammals, including cattle, sheep and pigs. Since FMD can cause mortality and reduce yields in economically-important livestock, many countries make strenuous efforts to prevent and contain outbreaks. In 2001, an FMD epidemic in the UK was eradicated using livestock movement restrictions and culling; vaccination was not used.
Now, Bryan Grenfell and collaborators have examined how reactive vaccination could be effectively deployed in a complex, heterogeneous environment where vaccination capacity is limited and vaccines are not 100% effective. Using mathematical models, and data from the 2001 UK epidemic, they simulated how alternative vaccination approaches might affect FMD epidemics.
They found that some reactive vaccination strategies can eliminate an epidemic more effectively than culling alone, even when vaccination capacity is limited. Interestingly, a simple strategy based solely on geographical distance and a simple time threshold (i.e. targeting farms closest to reported cases, within 10 days) appears to be more effective than more complex strategies (involving ring vaccination and prioritizing vaccination efforts by date of infection).
Written By: Michael J. Tildesley, Nicholas J. Savill, Darren J. Shaw, Rob Deardon, Stephen P. Brooks, Mark E. J. Woolhouse, Bryan T. Grenfell, & Matt J. Keeling
Journal: 440: 83-86
Journal Reference: 440: 83-86
Paper Id: 10.1038/nature04324