ABSTRACTS AND REPORTS.

the cortical substance. These were visible through the capsule; and bore a close resemblance to tubercles. The spleen also contained a tumour of con­siderable size.

Extensive lesions were present in the thoracic cavity. The costal pleura was covered with tumours, some being as large as a pea, but most of them smaller. These were round and projecting, and could easily have been mistaken for tubercles. More numerous tumours of the same sort were present on the upper face of the sterum, and the prepectoral lymphatic glands were enlarged . and invaded.

The lungs were firm and inelastic, and the lung tissue at first sight appeared to be diffusely infiltrated with a carcinomatous growth. Closer inspection showed that the new tissue was composed of very small greyish-white opaque growths. These were non-caseous, but in spite of this they might without histological examination have led one to suspect tuberculosis rather than carcinoma. -(lOid.)

THE NON-IDENTITY OF HUMAN AND AVIAN DIPHTHERIA.

M. GUERIN has carried out an investigation bearing on the etiology of avian diphtheria, and has thereby obtained further proof that the disease is etio­logically distinct from human diphtheria.

When one examines microscopically a cover-glass preparation made from the false membrane which forms in a fowl or pigeon, one is struck with the great variety of. bacteria present-micrococci, short and long bacilli, as well as numbers of mould fungi and protozoa. The diversity of these organisms, and their more or less frequent occurrence according to the case, explain the great diversity of opinion with regard to the etiology of the disease.

Most authors who have wished to demonstrate the specific nature of a par­ticular bacterium found by them in the lesions have succeeded in experi­mentally producing false membrane by excoriating the mucous membrane <;If the pharynx in healthy animals and rubbing some culture of the organism in question into the wounded surface. There is, however, nothing convincing in such a result, since a variety of different bacteria may lead to the develop­ment of false membranes when they are thus inoculated. This method of inoculation, moreover, never leads to the development of the citron-yellow fibrinous deposits on the pleura, air-sacs, peritoneum, and oviduct, which are characteristic of avian diphtheria. Avian diphtheria is a general disease, and the majority of the organisms which have been regarded as the cause of it have no tendency to become generalised throughout the body.

A different method of procedure has enabled M. Guerin to detect in every case the presence of the same particular bacterium. The method is as follows ;-

From the pharynx, pleura, air-sacs, or peritoneum of a diseased fowl sacrificed for the purpose, one takes a small quantity of the yellowish fibrinous deposit characteristic of the affection. Preferably the material is taken from the air-sacs, as in that position it is generally less contaminated with acci­dental bacteria than the membrane formed in the pharynx. A piece of false membrane thus selected is triturated with a little distilled water in a sterile vessel. A quarter of a cubic centimetre of the liquid thus obtained is injected into tbe connective tissue of the lower eyelid of a young pigeon. In from ten to twelve hours afterwards the seat of inoculation has acquired a yellowish-white colour, owing to the afflux of a considerable number of leu­cocytes to the part. The eye is half-closed, and the lachrymal secretion is increased in amount. In the majority of cases the virulence of the material inoculated is not sufficient to cause the death of the experimental bird.

ABSTRACTS AND REPORTS.

After forty-eight hours the pigeon is killed, and one collects in a sterile tube the membranous production which has been formed on the inner sur­face of the lower eyelid. From this, proceeding as before, a second PIgeon is inoculated. After the third or fourth passage the pigeon dies within twenty-four hours from a disease which has become septicaemic, owing to the increased virulence of the causal agent. This agent, which is always the same, and found in every case, is a bacterium morphologically resembling the bacillus of fowl cholera. The following are its characteristics. Cocco­bacilli, non-motile, not stainable by the method of Gram, do not liquefy gelatine or coagulatemilk. The reil.ction of milk in which the organism is cultivated is not changed. No growth on potato, no formation of indol, does not alter the tint of litmus agar. The organism is facultatively aerobic or anaerobic, and its cultures exhale a special odour. It is further distinguished by being very exacting with regard to the conditions of life, and exhibiting a marked inconstancy of virulence. .

Numerous experiments ha.ve shown that of all the common domesticated birds the pigeon is the most susceptible to avian diphtheria, and it is by suc­cessive passages through this species that Guerin has succeeded in con­siderably exalting the virulence of the microbe, and in giving it a fixed character. If a pigeon is inoculated under the skin or into the peritoneum with about 5 cc. of such a virulent culture, death takes place in from twenty­four to thirty-six hours. The lesions observed at the post-mortem are those of an extremely rapid septicaemia. All the tissues and juices of the body contain a considerable number of the bacteria, but one never observes the macroscopic lesions which are characteristic of the natural disease.

However, Guerin has succeeded in reproducing all the serious localisations of avian diphtheria by allowing the experimental pigeons to become infected by ingesting food or liquid to which virulent cultures in bouillon-serum had been added. If the birds are young or not very resistant, such as pigeons, this method of infection determines in three or four days a very acute septicaemic form of disease. If the animals are older the symptoms vary according to the localisation of the lesions, which in every respect simulate those of the natural chronic disease.

When the birds are fed with infected materials one can observ~ during the first few days the appearance in the mouth or pharynx of one or several patches of false membrane. Some days later these may be eliminated and disappear, or they may serve. as the point of departure of a proliferating lesion, which in some cases terminates in generalisation of the causal agent.

In other subjects one finds extensive lesions of the lungs and pleura. The lungs present foci of caseous pneumonia. A thick yellowish-white false mem­brane lines the walls of the chest, and sometimes one finds the mucous lining of the air-sacs similarly covered.

However, the majority of the subiects of experiment show after about three weeks areas of necrosis in the liver, the colour of these being at first yellowish­white, and afterwards during the last days of life of a dull green colour.

In exceptional cases the ingestion of the microbe set up peritonitis, with a thick and very abundant exudate containing large numbers of the specific organism. In a small number of pigeons arthritis developed in the scapulo­humeral and humero-radial joints, which lesions are. well-known to breeders of carrier pigeons. .

The faeces of birds thus infected are virulent, and it is very easy to isolate the organism from them. For this purpose it suffices to take a small quantity of the faeces mixed with a little sterile water, and to inoculate t cc. of the mixture under the lower eyelid of the pigeon. As a rule the first pigeon thus inoculated does not die, but after three or four passages the false mem­brane forms at the point of the inoculation, and from it one succeeds in isolating the causal microbe in a state of purity. The virulence of the faeces explains

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66 ABSTRACTS AND REPORTS.

why the ocular lesion is so frequent in fowls infected with this disease. Apart from the numerous chances of direct infection, fowls and pigeons inoculate themselves owing to their habit of frequently scratching their eyelids with their feet soiled with excrement.

With regard to the transmissibility of the disease to man, the only authentic observation of the kind is one reported by MM. Loir and Ducloux. These authors in studying avian diphtheria found at a farm an infant suffering from pseudo-membranous laryngitis, and they alleged that the causal agent of the disease in the child was identical with the one which they found in the false membrane of fowls affected with avian diphtheria on the same farm. However, the description of the organism given by these authors indicates that it was one of the colon group of bacilli, representatives of which class are often fonnd in the most various kinds of false membranes.

M. Guerin has himself paid particular attention to this subject, and his ex­perience has convinced him that the disease is not transmissible to the hnman subject. In certain districts in the north of France the breeding of game­fowls for cock-fighting is very common among the peasants and workmen; and, as is well known, that breed is particularly susceptible to avian diphtheria, large breeders sometimes losing as many as 40 per cent. of the birds from it.

M. Guerin has seen some of these fowls severely affected with avian diph­theria kept in the room used by the family for taking their meals, and observed the children and others feeding out of the hand fowls that were rendered blind by the diphtheritic conjunctivitis; but in spite of this and other oppor­tunities of infection he has never seen any evidence that the disease could become transmitted to children.

Although it thus appears to be justifiable to assert that avian diphtheria is not transmissible to the human subject, it has been stated that the Klebs­Loeffler bacillus may co-exist with the bacillus of avian diphtheria in the false membrane found in fowls. Some of the observations made with regard to this point apparently cannot be placed in doubt, but Guerin holds that such cases are exceptional, and that the Klebs-Loeffler bacillus isolated in these circumstances has generally been devoid of pathogenic properties, and only with difficulty identified with the bacillus of human diphtheria. Out of sixty­eight examinations which Guerin was able to make, he was able in two cases to isolate from the false membranes of fowls affected with avian diphtheria a microbe morphologically similar to the bacillus of human diphtheria, but it absolutely failed to produce any toxin. That also was the case with the bacillus isolated in similar conditions by Malvoz. Ferre of Bordeaux, who has most frequently found the two bacilli in association. alleges that he has seen in the diseased fowls paralysis of the legs similar to what is produced by inoculation with the toxin of human diphtheria. Guerin has never seen this, and he records that he has treated more than two hundred fowls affected with avian diphtheria by injections of human anti-diphtheritic serum, but with no greater effect than was produced by treating a parallel series of diseased birds with normal serum of the horse. He has tried with encourag­ing results a method of sero-vaccination intended to protect fowls against avian diphtheria. The principle of this vaccination consists in sensibilising the bodies of the bacteria by mixing them with a sensibilising serum obtained after practising intravenous and intra-peritoneal injection of large quantities of culture into a horse. Such serum, even in very small dozes, renders the bacteria capable of bcing ingested and destroyed by the leucocytes of normal fowls. Cultures thus sensibilised are very well tolerated in the peritoneum. This anti-bacterial serum also possesses the curious property of preventing the growth of the organism of avian diphtheria when a drop of it is added to bouillon serum, which is otherwise the most suitable medium for its growth. This fact cannot be attributed to agglutination, for the serum does not agglutinate cultures already made.-(Recueil de MM. Vet., Jan. 1903.)