Epidemiology and Control of Aujeszky’s Disease in the Republic of Ireland

The relationship between Aujeszky’s disease and changes in the pattern of pig production in the Republic of Ireland is discussed. The emergence of Aujeszky’s disease in the 1970s as a serious economic problem was associated with the establishment of large intensive units. Eighty primary cases of disease were diagnosed between 1973 and 1980, more than half of these occurring in herds ranging in size between 100–1 700 sows. All zoosanitary measures failed to halt the advance of Aujeszky’s disease and, in addition, serological surveys indicated that subclinical infection was widespread.