The molecular biology of the morbillivirus (measles) group.

The morbilliviruses are a closely related group of important human and animal pathogens. The best known members of the group are measles virus in man and canine distemper virus in dogs. The group also includes two other serious animal diseases, rinderpest or cattle plague and peste des petits ruminants in sheep and goats. The latter viruses are of great economic importance in Africa, Asia and the Middle East. Persistence of these viruses in some form is a possible mechanism whereby life-long immunity is conferred on an infected individual. In addition to the severe, often fatal, acute disease these viruses can, in rare cases, lead to a fatal chronic disease of the CNS. Molecular biological studies will be described which are beginning to elucidate their evolutionary relationships and to provide a basis for understanding the role of individual virus genes in pathogenesis.