in exceptional cases, be cultivated on bovine tissues. The experiments are so difficult to carry out that many have failed, and have positively refused to believe in the successful results of others. Variolation of the cow is nevertheless a fact, and so marked is the effect of cultivating the small-pox virus upon a soil which is foreign to it, that the highly infectious disease in man becomes transformed in cattle into a mild disease which is not infectious. The effect of a foreign soil is also illustrated in the result of inoculating sheep-pox in man. This highly infectious disease of sheep, when grafted on human tissues, is also transformed iuto a mild non-infectious disorder.

We can take it for granted that in exceptional cases human tubercular virus can be experimentally grafted on cattle, and we have good reason to believe that in exceptional cases bovine bacilli may invade the human tissues. I refer to those rare cases in which there has been accidental inoculation. Veterinary surgeons, butchers, and others whose occupation brings them into contact with diseased cattle, do suffer from tubercular nodules in the skin, which contain tubercle bacilli, undergo caseation, and disappear. I am convinced that human infection with the bovine variety of tubercle can only be quite exceptional: if it were not so, the inhabitants of every country in the world in which bovine tuberculosis is prevalent would be decimated by tubercular disease. Tubercle bacilli occur with frequency in milk, cream, butter, cheese, and I have already given you some idea of the quantity of meat derived from animals with more or less tuberculosis.

TUBERCULOSIS IN CHILDREN,

I would next draw your attention to the theory that tuberculosis in children is necessarily due to infection from the milk of tubercular cows. Those who advocate this view appear to have entirely lost sight of the opportunities for inoculation from a human source. Tuberculosis of the digestive tract may result from swallowing sputum when there is concurrent disease of the lungs, and in many other ways. There are obviously many paths by which a child may be infected by the mouth with bacilli from a human source. A tubercular mother may take little or no precaution in nursing her children, and the habit of tasting food before giving it to an infant suggests a channel of infection. Various objects, contaminated by consumptive sputum, may find their way to the mouth of a child. London physicians, who have had enormous experience with patients suffering from consumption, of all ages, are by no means ready to accept the

milk theory. Sir Richard Douglas Powell, one of the most cautious and scientific of living physicians, in his evidence before the royal commission, stated that he had not met with any cases in his experience which would connect consumption in man with the use of milk and meat from tubercular animals. Dr. Goodhart, consulting physician to the Evelina Hospital for Children, was of the same opinion. I certainly am not prepared to attribute tuberculosis in children to a bovine origin, especially as the experiments of Nocard and others have shown that when the milk of the tubercular cow is mixed with the milk of healthy cows it is no longer virulent to experimental animals. In order to accept the theory that tuberculosis in children is due to cow's milk, we should have to believe that in every instance the milk supply had been obtained direct from the udder of a tuberculous animal without being mixed with the milk of other cows.

I consider, nevertheless, that milk from cows suffering from any diseased condition of the udder or teats is unwholesome, and I maintain that when we pay for pure milk we are entitled to have it. We want the doctrine of absolute cleanliness to reach our dairies, both public and private. On no account should any "waster or "piner," or cow suffering from any disease affecting the milk, be admitted into the herd. Registration and inspection of dairies are of great importance, but with or without Government inspectors I think the public might to a great extent protect themselves. It would be a distinct advantage to adopt the Danish system of co-operation. towns like Brisbane small dairymen should combine to form large model dairies. They should invite inspection of their premises and farms. They would find it to their own advantage to employ a veterinary inspector. The public would be willing to pay a higher price if they had a guarantee that the cows were healthy and that every precaution had been taken in the collection, in the transit, and in the delivery of the milk. A great deal has been said upon the necessity of boiling milk. Except in time of epidemics it is not a practice likely to be generally adopted. Pure fresh milk is an ideal food, and the boiling of milk alters its composition. It is then very unpalatable to many people, and is not only unsuitable, but in many cases dangerous, for infants. Neither Dr. Powell nor Dr. Goodhart were prepared to recommend the boiling of all milk. From their evidence we may gather that they had other causes of consumption in their minds. They insisted upon the fact that tuberculosis of the bowels is almost unknown in very young children, and it is not very

common even in children from five to ten years old. Dr. Goodhart laid great stress upon the fact that tuberculosis in children was very common when there was a distinct family history of tubercle, and it was quite common also to find children becoming tuberculous after measles, bronchial-pneumonia, whoopingcough, and intestinal catarrh.

I would draw attention to the fact that negro children in the West Indies suffer from tubercle, and they have very little milk, and this, owing to the tropical climate, is almost always boiled. Tuberculosis in children in England is largely a disease of the poor. Though it attacks all classes, it is extremely common among the London poor and in all our over-crowded towns. The disease among the poor is attributable more to the want of milk than to the possible occurrence of a few stray bacilli. Plenty of milk, good nourishing food, better hygienic surroundings, will with certainty diminish the number of tubercular children in England. As the slums are removed from our over-crowded cities, and when the problem of the better housing of the poor has been solved, we may confidently expect to see a steady diminution of consumption. In Brisbane and other growing towns in Queensland it should be the care of the Government, of municipal authorities, and the public that the insanitary conditions which we have inherited in the old country should never be allowed to arise.

FLESH OF TUBERCULOUS ANIMALS.

As regards any danger from consuming the flesh of animals with tuberculosis, I believe it is practically nil. There has not been a single case recorded of tuberculosis contracted by eating tuberculous meat. Jews have a very thorough system of meat inspecton, and yet they are by no means free from tuberculosis. In the course of my travels in the West Indies I found that the negroes were very liable to consumption, and Dr. Williams, of Demerara, pointed out to the royal commission that the Hindoo coolies also suffered very severely. Yet Hindoos eat very little meat of any kind, and the negroes eat meat in very small quantities, and then it is beef or salt pork imported from America and well cooked before it is eaten. They, however, take very little care to protect themselves from chills, and they live for the most part in small and badly-ventilated buildings. We are justified in concluding that if the carcase is well nourished the meat is perfectly wholesome, in spite of the existence of local deposits of tubercle in the viscera and glands which should, of course, be condemned. The views of extremists cannot be carried into

effect. It is sometimes argued that though an animal may be in prime condition, if there is a single tuberculous nodule the carcase ought to be destroyed. In my opinion there would be no justification for the wholesale destruction of such valuable food. Compulsory destruction of every animal with the slightest indication of tuberculosis would ruin the farming industry. No Government would face the question of compensation for every case of tuberculosis, however slight the lesion. Such a course would involve the destruction of an enormous proportion of the cattle of the United Kingdom, and create a meat and milk famine. To secure perfectly healthy cows, thus saving much loss and ensuring the supply of pure and wholesome milk, will be a splendid work for veterinary surgeons and breeders of stock to undertake, and one to which they should direct all their energy. It can be confidently asserted that there can be no better recommendation of Queensland meat than a very high standard of health in Queensland cattle, and the percentage of tuberculosis in cattle in Queensland would appear to be extremely low. I find in the reports of the Board of Agriculture out of 21,768 cattle slaughtered the proportion of tubercle was 1.1 per cent.

In another report of 27,905 slaughtered, the percentage of tubercle was 9 per cent. But as I have already pointed out, it is difficult to arrive at a correct estimate from the published

returns.

64

SO-CALLED CANCER IN CATTLE.

It is absolutely necessary to differentiate in every instance the disease known as actinomycosis. I have already referred to the use of the word "cancer" in the reports of the meat inspectors. I regret to find that this popular term is still made use of. Probably those who use it little realise how damaging it is to the meat industry of the State. Last year there was a correspondence in the Times in which it was suggested that the increase of cancer in England was due to eating the flesh of cancerous animals imported from the colonies. I took an early opportunity of pointing out the absurdity of suggesting any connection between so-called cancer in cattle and cancer in the human subject. Many years ago I published an exhaustive report upon actinomycosis, which is prevalent in England. I pointed out that various manifestations of this disease were known to farmers and breeders as "cancer of

local inflammatory affection associated with the presence of a characteristic fungus known as the streptothrix actinomyces. The disease has no relation whatever to cancer in the human subject. It is this disease which is met with in Queensland, and it is most unfortunate that the public should be alarmed by any reference to cancer. I trust that in all future reports of the meat inspectors that the popular term "cancer" will be left out altogether, and that the scientific name for every disease will be given. Actinomycosis, though common in cattle, occurs also, though rarely, in man, and, as in the case of tuberculosis, it has been suggested that the disease is derived from cattle. It is, in my opinion, a distinct variety. I do not accept the theory that men and animals infect each other with actinomycosis, but I believe that they contract the disease quite independently, and that the microorganism is derived from some source in common. And, further, the flesh in these cases is perfectly wholesome, and only the tongue, or other part affected, need be destroyed.

PSEUDO-TUBERCLE BACILLI.

We have not only to distinguish actinomycosis from tuberculosis, but we must in future pay close attention to distinguishing the tubercle bacillus from some recently discovered and closely allied bacilli. There is no doubt that the reports of the discovery of tubercle bacilli to an alarming extent in milk and milk products, and in the dust of rooms inhabited by consumptive patients, will have to be modified. After the first discovery of the tubercle bacillus, all rod-like organisms with the same tinctorial characters were pronounced to be tubercle bacilli, with the exception of the leprosy bacillus and a bacillus found in certain secretions. Further investigation of some of these bacilli have given very striking results. The first discoveries in this direction were made by Petri and Rabinowitch, who succeeded in showing

that there was a bacillus in butter with all the general characteristics of the tubercle bacillus, and further, the inoculation of this bacillus in guinea pigs produced lesions, which to the naked eye and under the microscope were very easily mistaken for tuberculosis. Korn and others have described other forms in butter and milk not materially differing from one another, and Moeller regards them as varieties of the socalled grass bacillus obtained from grasses and

dust. The latter was first obtained from Timothy grass, and is known as the Timothy bacillus. It cannot possibly be distinguished microscopically from the tubercle bacillus. It is granular, and exhibits branching and club-like swellings; it stains exactly like the tubercle

bacillus; and the cultures, though differing at first, after passage through animals strongly resemble those of tubercle. In guinea pigs the lesions are similar to those set up by the butter bacillus, and in rabbits they are very difficult to distinguish from true tubercle, owing to the formation of giant cells and epitheloid cells and caseation. Another grass bacillus is similar in staining reactions to the tubercle bacillus, but it is rather thicker and has a special tendency to form threads. It produces in guinea pigs lesions similar to those caused by the butter bacillus. Another pseudo-tubercle bacillus has been isolated from manure and from the excrement of cows and other herbivora. Other bacilli of this class have been found by Fraenkel and Pappenheim in pulmonary gangrene and other morbid conditions of the lungs, and by Moeller in nasal and pharyngeal mucus.

PREVENTION OF CONSUMPTION.

With regard to the prevention of consumption, this must be left principally to the sanitary inspector and the medical officer of health. We must not concentrate all our energies upon the destruction of tubercular sputum, but give much more attention to those insanitary conditions which are responsible for the causation of tuberculosis. This is a matter which in Brisbane can be safely left in the hands of the energetic Commissioner of Health. Dr. Ham has before him a career of great usefulness in this city; but if he were to do nothing more than what he has already achieved he would deserve to be remembered with gratitude by the public of Brisbane. I refer more particularly to the institution of a Queensland branch of the London Sanitary Institute the recognised authority for granting certificates qualifying persons as sanitary inspectors. This will have a far-reaching effect in obtaining and maintaining a high state of sanitation in this town. I regard the trained sanitary inspector as the most formidable opponent of diseases such as diphtheria, typhoid, cholera, plague, and yellow fever, which flourish wherever insanitary conditions prevail. If only sanitary inspectors could, without let or hindrance, carry out their duties under the direction of one central authority, we should soon hear of a reduced death-rate and far greater immunity from epidemic diseases. The work of sanitary inspectors is one which ought to be more fully appreciated by the public, and, instead of hindrances, facilities should be put in their way when carrying out duties which involve the general health of the community and the saving of many human lives.

As regards the relation between tuberculosis and insanitary conditions, we have some

evidence forthcoming from the study of the disease in animals. Tuberculosis, for instance, is peculiarly liable to occur among birds and animals kept in captivity; poultry and guineafowls, and ostriches and emus and other birds in zoological gardens, develop tuberculosis; monkeys in captivity, pheasants in preserves, and rabbits in overcrowded warrens sometimes die in great numbers. These examples point to the conclusion that confinement, overcrowding, defective ventilation, heredity, and breeding in and in are powerful factors in rendering the tissues prone to tubercle and a fitting soil for the invasion of the bacilli. We must also remember the danger of damp houses and the effect of a cold and foggy climate. In addition to general insanitary conditions, I desire to draw particular attention to the influence of alcoholism. This was brought most forcibly before the London Congress in an exhaustive paper by Dr. Brouardel. The influence of previous diseases has been urged by Dr. Goodhart; and special trade оссираtions which involve inhalation of dust of various kinds must not be overlooked. I trust that much weight will be given to these matters by the Queensland Society for the prevention of consumption.

HEREDITY.

I should like to say a few words on the subject of heredity. Heredity is of two kinds. There is hereditary pre-disposition and hereditary transmission. Inherited susceptibility renders many liable to the development of tuberculous disease. Family history plays a very important part in tuberculosis.

Sir

Richard Powell stated to the commission that, in his experience, 48 per cent. of the cases in hospital suffering from tuberculosis had a previous history of hereditary tuberculosis. Dr. Klein and Mr. Victor Horsley are convinced that there is direct transmission of the virus of tubercle in some cases, and that it may exist for many years in a latent form. In connection with the question of heredity, some interesting observations have been recorded upon tuberculosis in birds. According to Dr. Baumgarten, a male bird on a poultry farm developed tuberculosis. All the chickens reared from this parent were tubercular. There was no evidence of infection with either human or bovine tubercle. An identical case occurred on another farm, and these instances have been quoted in support of the theory of direct transmission of the virus from the parent. Tuberculosis is not a common disease in calves, and it seems probable that those cases which do occur are mostly, if not entirely, the result of hereditary transmission.

CONSUMPTION NOT INFECTIOUS BUT INOCULABLE.

In conclusion, I would like to draw attention to the theory upon which so much stress has of late been laid, viz., that consumption is infectious. I feel very strongly that this is most misleading, and I think we ought to do all we can to allay the public anxiety which has arisen from the belief that consumption can be caught like scarlet fever. To compare it also to typhoid fever is a great mistake. In typhoid epidemics at home, in India, and recently in South Africa, we know that those in health and out of health fell victims to the disease when they took the poison in food or water. Tuberculosis is not infectious, but it is an inoculable disease. In the Brompton Hospital, in London, it has been found that among nurses, porters, physicians, surgeons, in fact among all those who have been in connection with it, the mortality from consumption is within the average of ordinary mortality. If tuberculosis were an infectious disease, and readily conveyed from person to person, the marriage of individuals who become, or are consumptive, would be a fruitful source of direct infection. We should hear constantly of instances in which married people had infected each other with tuberculosis. There is a great difference between natural infection and experimental inoculation, and to this we should attach the greatest importance.

It cannot be too widely known how virulent is the sputum of consumptive patients when inoculated in susceptible animals, and the habit of spitting in public places, and railway carriages, and other conveyances, should be prohibited. It is a disgusting habit, but there is no need to create a panic or raise an outcry for legislation, making spitting in public places a matter to be dealt with in the police court. The sputum of consumptive persons should be disinfected. A good deal of attention has been drawn to the danger of sputum when dried and raised in dust. The virulence is greater when the sputum is moist, and when it has not been exposed to sunlight. That the virus of tubercle is scattered far and wide, and is a danger to all, is not a theory which is supported by experiment or experience. For example, sputum dried and disinfected by the powerful action of the Australian sun, will be rendered inert. Dr. Ransom maintains that in a well-ventilated room sputum is harmless. Tuberculous sputum kept in the ventilating shaft of a hospital proved virulent to rodents, but similar sputum in a well-ventilated and well-lighted room became absolutely harmless. It is no doubt owing to this exaggerated idea of infection that there have been such extreme proposals as the New Zealand Act excluding tubercular immigrants. It is probably due to the same cause that there

is some prejudice in Queensland against the building of sanatoria for consumptives. There is not a shadow of foundation for the theory that there is danger to the inhabitants of a township if a sanatorium is erected in the neighbourhood. I trust there will be no opposition to erecting sanatoria for the poor and for paying patients. Bright sunshine, invigorating air and cheerful surroundings are conditions which compensate in some measure for separation from family and friends, alleviate the sufferings, and give hope in many cases of permanent recovery.

CONCLUSION.

In the remarks I have made to-night I have touched upon many controversial points, and I have endeavoured to indicate the lines upon which further research is required. I trust that those engaged in scientific inquiries in Queensland will help to throw light on these points. The report of the new Royal Commission now sitting in London will be awaited with interest, but in the meantime there is no uncertainty as to the course to be adopted by those responsible for the public health. Whatever the result of that inquiry may be as regards the relation of bovine to human tuberculosis, we know that there are many factors in the production of this disease.

The removal of insanitary conditions by the co-operation of the public with sanitary officials will secure for Brisbane the enviable position of being conspicuous among all the great cities of the Commonwealth, on account of its low death rate and practical immunity from all epidemic diseases.

THE WIDAL REACTION.

ITS PRACTICAL WORKING AT SYDNEY HOSPITAL.

BY

J. L. T. Isbister, M.B., C.M. (Adel.), late Resident Pathologist;

C. V. Bowker, M.B., Ch.M. (Syd.), Medical Superintendent and late Resident Pathologist; and

H. Skipton Stacy, M.D., Ch.M. (Syd.), late Resident Pathologist.

ONE of the most common beliefs about the widal reaction is that if the result is not "positive" it must be undoubtedly "negative." Now this is far from being the case. There are a certain number of reactions which are on the borderland between the two, and it is with these that judgment and great experience of the reaction are necessary. For instance, after the lapse of, say, 50 or 60 minutes, there may be a few small clumps

They

present. These will hardly be sufficient on which to call it a positive reaction, yet we have no doubt that, provided the culture be good, these clumps have some significance. may be interpreted in one of two ways-(a) either that the patient is in the early days of an attack of typhoid, or (b) that he has had typhoid previously, some of the anti-toxin which he then formed remaining in his blood and exerting a feeble clumping action. In a few cases patients suffering with chronicdiseases have given this very feeble clumping reaction, and we have not been able to definitely trace a past history of typhoid, but as frequently the disease is mild and goes by other names, the question is by no settled by the patient's statement. grounds for saying that even slight clumping has some significance is that we have watched the action of blood of numberless diseases on the typhoid bacilli, and, with the exception of a few cases noted elsewhere, there has been no sign of clumping after an hour or more.

means

Our

It is impossible to write down what extent of clumping constitutes "positive; " different observers might look at the same reaction (provided it is not marked) and yet have different views as to the result. As a rule, in our experience, the bacilli, if they are going to clump, will at least commence to do so within twenty minutes; in those cases where they do not, the clumping, if it does appear later on, is never very marked and not of great diagnostic value. It is not necessary for all the bacilli to be clumped; even in marked reactions it is common to see some free and actively mobile. Preceding the clumping thereis always a diminution of motility, but too much stress should not be laid on this alone, as without the addition of blood the bacilli tend to become much slower in their movements after ten minutes or so. The intensity of the reaction is not always in accordance with the severity of the disease.

Day of the disease on which the reaction appears. This is impossible to fix, since it varies so much. This we can say, however, that it is not usually present in the first week. We frequently get it about the eighth day, but never well marked till at least a few days later. The longer the patient has been ill the more marked the reaction, and it is not at all uncommon for the clumping to have taken place before it can be examined under the microscope. On the other hand, there are a few cases of typhoid which fail to give it throughout their course, but show it during the relapse. This has happened in several cases, and makes one wonder whether the relapse is in any way due to the deficiency of the anti-toxin in the blood. Unfortunately