A Taxonomic Study of Pasteurella septica, especially of Strains Isolated from Human Sources

Abstract

SUMMARY:The characteristics of fifty-nine strains of Pasteurella septica, mostly derived from human lesions, were analysed by an electronic computer. The cat strains showed a high degree of similarity to each other, while the dog strains were more variable. Most human infections other than those due to bites seem to be due to strains which probably originated from cats. The analysis suggests that P. septica is distantly related to P . pestis and P . pseudotuberculosis but that the two latter are closely related to each other.Most text-books of systematic bacteriology include in the genus Pasteurella the three organisms Pmteurella septica, P. pestis and P. pseudotzlberclulosis and sometimes also the causative organism of tularaemia. They usually give the haemorrhagic septicaemia bacterium as the type species of the group. Topley and WiZsm's Principles (1955) pointed out that it is very doubtful whether the recognition of several distinct species is justified. There are no consistent biochemical or serological differences detectable by ordinary methods between strains of P. septica isolated from different animals; to all appearances these strains are identical. A better description of the organism would be of value; it is of considerable veterinary importance and under certain circumstances may also be a human pathogen (Cawson & Talbot, 1955). The organism is a normal inhabitant of the nose and throat of dog and cat (Smith, 1955); dog and cat bites, and more rarely those of other animals (McGeachie, 1958) form one group of the human infections. The other group is made up of 'internal' infections, that is, infections not involving direct inoculation as with a bite; the majority of these are associated with the upper respiratory tract.Systematic analysis of a large number of strains of the species by orthodox methods is not a satisfactory procedure because the similarity must necessarily be close and personal bias is likely to influence the result. The principles of classification described by Sneath (1957a, b) are based on the assumption that each feature of an organism has equal taxonomic significance. A large number of characteristics of a large number of strains can be compared easily by a mechanical device, such as an electronic computer, and the degree of * Present address : Department of Pathology, Kingston Hospital, Kingaton-on-Thames, surrey.

Numerical Taxonomy of Haemophilus and Related Bacteria

“…It is well known that Actinobacillus lignieresii and A. equuli are close species, and this has been recently discussed by Ross et al (45). The findings on the Pasteurella strains studied are in fair keeping with previous numerical taxonomy on the genus (52,60,62), and they confirmed the distinction between Pasteurella and Yersinia. The behavior of types A and T of P. haemolytica Newsom and Cross in the different analyses adds t o the growing evidence, reviewed by Shreeve, Ivanov, and Thompson (48), that these types may be less similar than generally thought and are possibly different species.…”

Recent Developments in Theoretical and Quantitative Taxonomy

“…They may therefore be said to be Adansonian in their basic philosophy, though several of these authors have certain reservations about equal weighting. These methods have been successfully applied in many groups of organisms, such as insects (Michener and Sokal, 1957), man (Cain and Harrison, 1960a), plants (Rogers and Tanimoto, 1960;Morishima and Oka, 1960), and bacteria (Sneath, 1957b;Sneath and Cowan, 1958;Hill, 1959;Cheeseman and Berridge, 1959;Liston and Colwell, 1960;Talbot and Sneath, 1960;Pohja, 1960;Bojalil and Cerbon, 1961;Colwell and Liston, 1961). This is not the place to describe in detail the methods, but, briefly, all of them are based on elementary forms of multivariate analysis, a technique which has been principally used in psychology, and in ecology (e.g., Goodall, 1953;Williams and Lambert, 1959) and also, interestingly enough, in linguistics (Ross, 1950).…”

Urinary tract infection with Pasteurella multocida in a patient with cat exposure and abnormal urinary tract physiology: Case report and literature review

“…A literature review of UTIs caused by P. multocitda revealed nine published cases with patient-specific information, summarized in Table 1 [4], [5], [6], [7], [8], [9], [10], [11]. There are also several earlier papers which mentioned the presence of urinary tract infection with P. multocida but did not provide details about the patient case or outcomes, and as such these are not included in our review [3], [12]. In six of the nine published case reports, preexisting urinary pathology was present, predisposing the patients to UTIs.…”