[Nosology, epidemiology and bacteriological taxonomy: salmonella infections as an example (author's transl)]

Salmonella infections are discussed as an example of the interdependence of the classification of infectious diseases on the one hand and the taxonomy of bacteria on the other. The term paratyphoid was first created as a name for a disease but was later turned into a common name for the cause and then refined into a specific epitheton of a species of bacteria. It was difficult to create terms for pathology as long as a reliable differentiation of related species of bacteria was not possible, so both a typhoid and an enteric form of paratyphoid fever were referred to, superimposing the clinical differentiation of typhoid fevers and food poisoning (enteritis infectiosa). Epidemiology and bacteriology cannot expect their classifications to determine the classification of bacteria on the level of genus and subgenus, but systematic bacteriology should not conserve or create species and subspecies that are unnecessary for applied medical bacteriology. The needs of epidemiology usually require identification and determination of serovar, biovar and phagovar of the individual strain, but for pathology it is important to classify series of strains on the basis of certain combinations of serovars, biovars, and phagovars as special forms.