The role of small ruminants in the epidemiology and transmission of foot-and-mouth disease.

Despite representing the largest part of the world's foot-and-mouth disease (FMD)-susceptible domestic livestock, sheep and goats have generally been neglected with regard to their epidemiological role. This is partly due to the often inapparent nature of the disease in these hosts. Nevertheless, their ability to become carriers represents a reservoir for further infection and spread of disease, and so trade of live sheep and goats present a major risk of entry of FMD to disease-free countries. Research and epidemiological studies continue to be necessary in order both to prevent the entry of the virus and to assist in control should the disease reoccur. This review concentrates primarily on more recent studies relating to sheep and goats and, in particular, considers the importance of these hosts in the overall epidemiology of FMD.