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appearances presented by the diseased animals-intra-vitam and post-mortem-differed from those usually regarded as pathognomonic for what is generally recognised as true Rinderpest. The absence of certain symptoms and the characteristic and constant post-mortem appearances coupled with the presence of a definite micro- organism in the blood and tissues have led us to the conclusion that the epizootic is something very different from Rinderpest, and required investigation. Accord- ingly we requested the Government, through the medium of the Sanitary Board, to grant us such facilities as would enable us to do so. Permission having been got, the enquiry was commenced early in June, of the present year. In the first instance it was our intention to investigate this disease with a view towards its prevention. However on undertaking the enquiry we found so much of interest in regard to the symptomatology, pathology and bacteriology of the dis ase that we considered it advisable to make a preliminary report on these questions only. In making this report we hope that we have so dealt with the disease as to show conclusively that the cattle epidemics here in Hongkong are not rinderpestic but of a different etiology. This report deals only with the question "What is the Disease ?" The important questions as to the modes of infection, curative treat- ment, and immunity against the disease have not been considered by us at present. As such questions can only be tackled after a thorough knowledge of the pathogenesis of the disease, we have left them to be dealt with at a future date.
At the commencement of our enquiry, the temperature of all the animals presented for slaughter at the Kennedy Town Cattle Depot was taken; all animals having a suspicious rise in temperature were at once isolated and placed under observation. The temperature of these animals was taken twice daily and symptoms as they presented themselves noted. Immediately the nature of the disease became evident the animals were quarantined in the old Tung Wah Mortuary, which is fitted up for segregation purposes. The condition and temperature of such animals were noted daily and on death occurring, a post-mortem examination was undertaken as soon as possible. This method of segregation of animals has been adopted by us since the commencement of the present enquiry and is still being carried on. This procedure was found necessary owing to the fact that the disease is most insidu- ous in its onset. It was a common occurrence to find an animal with a temper- ature of 106° F. and with no other manifestation of ill health. The method in addition was of advantage in that all cases of sickness were discovered and that no suspicion could arise as to the quality of meat sent out for consumption. It may be as well at this point to state that so far we have alsolutely no data as to the com- municability of the disease to man. Inspectors, boys and coolies who were daily in contact with the disease have so far enjoyed perfect health.
Up to the date of writing this report, 224 animals (experimental included) have been either infected or attempts have been made to induce infection. These animals consisted chiefly of bullocks. In connection with the particular species of animal affected it is important to note that during the course of this epidemic only one buffalo contracted the disease, but this coincidence may be accounted for by the fact that during the summer very few buffaloes have been brought into the Colony for slaughter.
The mortality amongst the affected animals averaged 70 per cent.
The disease as met with during our investigation, was in the majority of cases an acutely fatal one. Death usually occurred within a week. In other cases the disease was of a more chronic nature, death occurring 10-15 days after the com- mencement of the rise in temperature.
An
In those cases in which recovery took place after the disease had run a typical course, the temperature reached its normal figure in about three weeks. Appendix (A.) is attached giving full details in regard to the symptomatology of the disease. The chief characteristics regarding this are rise in temperature, diarrhoea of a mucoid and bloody character, rapid emaciation accompanied by great weakness and prostration. No lesions of the mouth, skin and feet have been observed. The diarrhoea commences in the majority of cases two days after the temperature has reached its maximum-vide Temperature Charts appended.
Post-mortem. The results are uniform, and characterised by congestion, in- flammation, ulceration and necrosis of the gastro-intestinal tract and by a hæmorrhagic condition of the visceral, deep and superficial lymphatic glands.