Limited effect of vaccine in foot-and-mouth model

Vaccination during the recent foot-and-mouth epidemic would have had little effect, according to a recently developed model of the epidemic. Researchers from the University of Edinburgh and Department for Environment, Food and Rural Affairs (DEFRA) developed a model to estimate the regional risk of transmission of the virus amongst livestock. However, when they explored vaccination strategies, they found that although vaccination in the early stages of the epidemic would have been advantageous, culling was more effective at limiting the epidemic. Their analysis showed that vaccination, even at high levels, during the later stages of the epidemic would have had little effect on transmission. Dr Keeling from the University of Edinburgh says that the team is ‘currently following up these initial results with a more extensive analysis of the use of vaccination’. The current policy of local culls was successful in their model, such that the number of infections was reduced by 50% compared with the numbers documented when infected animals alone were killed. Science (2001) 294, 813–817 AL