As most cattle have only been vaccinated ≤2 times, a more potent vaccine able to deliver greater immunity after only one or two doses would greatly increase population immunity. Immunity gaps will still exist as each round of mass vaccination is likely to exclude a quarter of all cattle. Prioritising repeated vaccination of young cattle, with high coverage, would help reduce this gap.

However, over-reliance on vaccination with limited movement controls or isolation of infected animals is not recommended as FMD virus is highly infectious and vaccine protection will still leave clusters of high susceptibility^7,13,48. Susceptibility is exacerbated if there is a high risk of exposure to new virus strains, against which the vaccine may not protect.

In many FMD-endemic countries livestock movement restrictions and biosecurity measures are difficult to implement. In this situation FMD control becomes heavily dependent upon vaccine protection. However, the extent to which FMD can be controlled by vaccination alone remains an unanswered question of global importance."

Knight-Jones, T. J. D. et al. Mass vaccination, immunity and coverage: modelling population protection against foot-and-mouth disease in Turkish cattle. Sci. Rep. 6, 22121; doi: 10.1038/srep22121 (2016).