The need to apply vaccines in different species – small ruminants

摘要

Foot and mouth disease (FMD) has been successfully controlled and eliminated in many parts of the world using conventional disease control measures, including vaccination of domestic animals. Potent vaccines have also been the mainstay in controlling outbreaks in non-enzootic regions. Several characteristics of FMD complicate the use of vaccines to control the disease. Not only are there seven serotypes, with little cross-protection between the serotypes, but genetic and antigenic variants occur within these serotypes. In addition, FMD virus can infect over 70 cloven-hoofed species, many of which are free-living wild animals. The role of sheep and goats in the epidemiology of the disease is poorly understood and perceived differently in different parts of the world. This perception is reflected in the vaccination policies applied in these countries. Cattle are generally the species of choice in vaccination programmes, while sheep and goats are vaccinated in only a small number of countries, and then mostly either for strategic purposes or as part of a routine disease control programme. The general assumption is that sheep and goats do not play a significant role in the spread of the disease or as sentinel animals to detect clinical disease. However, this assumption does not hold true for all circumstances or under all epidemiological conditions. This paper describes the potential circumstances under which the vaccination of small livestock should be considered to mitigate the risk of viral spread or to contain an outbreak of the disease.