[Chicken feed contaminated with Salmonella enteritidis in a small egg-producing farm as source of a chain of infection in man--problems in tracing the mode of transmission].

After having eaten rissoles containing eggs from a small laying flock two men fell ill with severe gastroenteritis by phage type 4 of S. enteritidis, one of them additionally with pancreatitis. In a sample of chicken feed and litter from the suspected hen-house we found the same phage type of S. enteritidis with the same virulence plasmid as in the faeces of the two patients. Because of the dramatic increase of human salmonellosis and the growing numbers of cases with serious symptoms, resulting from the enhanced invasiveness of the dominant species S. enteritidis, more effective defence reactions against the spread of enteritis-salmonellas are required. The most important measure would be the general decontamination of the mixed feed just before sending it to the farmer. Contaminated feed is the primary source of salmonella infection to livestock and - by means of food of animal origin also to man.