Marek’s Disease Research—History and Perspectives

INTRODUCTION MAREK’s disease (MD), a disease of chickens characterized by proliferation and neoplasia of lymphocytic tissues, continues to be of major economic importance in commercial flocks throughout the world. Although this disease has been studied intensively since its initial description by Marek (1907), only in the last decade have attempts to identify its cause and develop measures for its control reached some measure of fruition. Because recent developments have been profuse, it seems appropriate at this time both to reflect on some of the major past achievements and also to contemplate the direction of future research in this dynamic field. This brief history is not intended to duplicate more comprehensive reviews available elsewhere (Biggs, 1968; Calnek and Witter, 1971), but describes instead some aspects of the evolution of recent progress in MD research. Several key developments will be considered, with particular emphasis on the circumstances of their origin and on…