The authors pay attention to the mode of transmission of salmonelloses in children under two years of age, where the highest specific morbidity was recorded. Using phenotypic (biochemical properties, sensitivity to antibiotics, phagotype) and genotypic properties (presence of plasmids) they examine five sporadic and seven epidemic incidences of salmonelloses in young children. The most frequent agent is Salmonella enteritidis, phagotype 8, plasmid 55 kb. Strains of S. enteritidis are isolated from the faeces of affected children, their family contacts, from food and the sick child's environment. Alimentary transmission by the incriminated food was detected from epidemic incidence where the vehicle were confectionery products contaminated by S. enteritidis. In sporadic cases in families also direct and indirect contact may have participated in the transmission of infection.