On the paratyphoid and “food-poisoning” bacilli, and on the nature and efficiency of certain rat viruses

The bacteriological classification of the principal cultures used in rat and mouse control in Great Britain

1. The six ‘viruses’, Liverpool, Danysz, London, Ready Rat Relief, Institut Pasteur and Ratin, which are the principal bacterial cultures at present employed for anti-rodent control in Great Britain, have been examined. 2. By means of reciprocal absorption tests all these six strains were found to be serologically identical with S. enteritidis Gaertner, antigenic structure, IX:gom:—. 3. From the results of the fermentation tests, which may be used to subdivide this serological type, Liverpool, Danysz, Ready Rat Relief and Ratin were assigned to the var. danysz subgroup; while the London and Institut Pasteur strains could not be distinguished from the classic S. enteritidis type. 4. Both of these subgroups are pathogenic for man, and evidence is cited which shows quite clearly that human cases of gastro-enteritis have been caused by the use of virus preparations. There are, also, reasonable grounds for believing that these bacterial types may be pathogenic for a number of domestic animals, including some poultry.

On the Paratyphoid Group of Bacilli

1. The term “paratyphoid group of bacilli” has been confined in the present enquiry to those strains which in their cultural characters and agglutination reactions are indistinguishable from B. suipestifer and B. paratyphosus (B). B. enteritidis Gaertner and B. paratyphosus (A) are excluded.

2. The strains of bacilli belonging to the “paratyphoid” group can be separated into two classes by means of the absorption method, namely one group identical with recognised, standard strains of B. suipestifer and one identical with standard strains of B. paratyphosus (B); and we regard these two bacilli as separate organisms.

3. In our experience, B. suipestifer has been found only in food or in outbreaks of acute illness attributable to food-poisoning, whereas B. paratyphosus (B) has been found in cases of paratyphoid fever or in persistent paratyphoid “carriers.”.

4. We are disposed to put forward the suggestion indicated by these observations, that these two organisms have a different distribution in nature, the normal habitat of B. suipestifer being the alimentary canal of the pig (and other animals) and of food derived from such animals, whereas the normal habitat of B. paratyphosus (B) is the human alimentary tract (including the gall-bladder).

5. The examination of cultures from the faeces and urine of 300 typhoid convalescents was completely negative, neither B. suipestifer nor B. paratyphosus (B) being obtained. These observations confirm those of other writers, and, apart from carrier cases, the occurrence of B. paratyphosus (B) in healthy human beings appears to be unknown in this country.

Our thanks are due to Drs Fisher, Trautmann, Uhlenhuth, Williams, Rommeler, Prigge, Schern, Friedrichs, Savage and Fowler, who have very kindly supplied us with strains of bacilli for investigation.

Natural Variation of B. acidi lactici with respect to the Production of Gas from Carbohydrates

Variations in bacteria may be said to fall into two classes (1) those which are temporary, and dependent on the environment, the bacteria tending to return to the original type when subculture is made on ordinary media; and (2) those which are fixed, and persist after repeated subcultures on ordinary indifferent media.

Suppurative Cholecystitis with Cholelithiasis in a Human "Carrier" of the Bacillus enteritidis of Gaertner

In a case of suppurative cholecystitis with cholelithiasis a bacillus was isolated from the pus, gall bladder, and stools which has the morphological, biological and cultural characters of B. enteritidis Gaertner. This bacillus is pathogenic for the rat, rabbit and guinea-pig, and gives rise to the characteristic lesions produced by the Gaertner bacillus. The serum of the patient agglutinated the three strains of bacilli isolated from the above mentioned sources and the original Gaertner strain in a dilution of 1 in 40. A serum, prepared by injecting B. enteritidis Gaertner (original strain) into a rabbit, agglutinated the three strains isolated from the case and the homologous bacillus in almost the same dilutions.

A serum prepared from any of the three bacilli agglutinates the homologous organism, the other two strains and the original Gaertner bacillus in almost the same titre. The sera homologous to allied organisms do not agglutinate these bacilli. Absorption tests confirm these results and prove that the bacilli isolated are identical with the Gaertner bacillus.

The chief points of interest in the case are that:

1. It forms a link in the chain of evidence showing that as in the case of the paratyphoid bacillus the B. enteritidis Gaertner may give rise, not only to the more acute toxic from of poisoning, but also to a sub-acute paratyphoid type of the disease.

2. It establishes the association of B. enteritidis Gaertner with suppurative cholecystitis and with cholelithiasis.

3. It proves that this bacillus may have its habitat in the gall bladder and be shed out at intervals into the faeces, in a manner exactly analogous to what occurs in the case of typhoid and paratyphiod infections.

The Absorption or Saturation test of Castellani: its applications in Sero-Diagnosis, and in the Recognition of Bacterial Species: A critical review

The Absorption or Saturation Test published by Castellani in 1902 is now becoming more extensively used by serological and bacteriological workers in European and American laboratories. Its use is also essential for the accurate study of certain tropical infections, so that it behoves all tropical workers to be familiar with this test. It is therefore believed that an account of the method together with a general review of the literature of the subject may not be out of place in this Journal.