Se analizan los seis focos de encefalomiocarditis ocurridos en porcinos de la provincia de Ciego de Ávila en el período de 1978 a 1991; predominó la presencia en pequeñas crías. Se estudian las encuestas serológicas realizadas en porcinos de la provincia con la técnica de inhibición de la hemoaglutinación, detectándose un 26% de serorreactores.Se investigan 485 trabajadores de porcino con la técnica de seroneutralización, reaccionando 101 para el 20,8% y 179 donantes reaccionando el 62%. Fueron más frecuentes los reactores a diluciones bajas. Los tres casos que reaccionaron a 1: 128 y más títulos presentaron síntomas.Palabras claves: Encefalomiocarditis, porcinosAbstractThe six main focuses of encephalomyocarditis in swine in the province Ciego de Avvila in the period from 1978 to 1991 were analyzed. It was found to be predominant in small breedings. The serological surveys carried out in the province using the technique of inhibition of hemoaglutination were studied and a 26% of seroreactors were found. 485 swine producers were studied using the technique of seroneutralization; 101 of them were found to react, which represents 20.8%. 179 donors (62%) also reacted. The reactors to low dilutions were found to be more frequent. The three cases who reacted at a rate of 1:128 and more titles had symptoms.Key words: Encephalomyocarditis, swine.