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production of the disease, and in the light of our present micro-biological know- ledge must be regarded as extraneous organisms isolated and fully described by investigators using somewhat defective technique.
17. The bacteriological examination of WRIGHT'S so-called primary lesion, i.e., damaged gastro duodenal mucosa resulted in the isolation of many rod-shaped bac- teria, the biology of which shewed them to be nothing more or less than ordinary intestinal micro-organisms. In summing up our bacteriological results, our inves- tigations strongly point to the conclusion that Beri-beri is not due to any micro- organism of the hitherto described types. Indeed we doubt if the disease is an acute specific infectious disorder. So far our results are against its being so.
18. Coming to the experimental part of the Report, the results of our attempts to induce the disease in any of the common domestic animals are decidedly a failure. In no single instance, out of over 50 miscellaneous experiments upon monkeys, pigs, calves, sheep, fowls, rabbits, etc., were we able to call forth even the shadow of a symptom or sign of Beri-beri.
19. Comparing the results of these experiments with the series carried out by DURHAM who also had negative results, it would appear that it is impossible to convey Beri-beri directly from man to animals. So far as published records are concerned, monkeys are the only animals which appear to have contracted the disease, and then only under natural conditions. These-the experiments of HAMILTON WRIGHT and published in a recent number of " Brain"-however, are isolated observations, and judging from the recent remarks of DURHAM in the "Journal of Hygiene" some doubt would appear to exist as to the real condition of the monkeys described by WRIGHT as suffering from Beri-beri.
With the
20. The question as to whether any animal can contract Beri-beri direct from man, or indirectly through some other channel nust remain open. Our own opinion is decidedly against the conveyance from man to animals. exception of HAMILTON WRIGHT'S experiments which must be received with due caution, there are no reliable records of Beri-beri in animals. Indeed it would be difficult to experiment along these lines with hope of success in the absence of the etiological factor and its point of invasion of the body.
21. Our experimental researches bring us further along the line of our con- clusions as to the non-micro-organismal nature of Beri-beri. Up to the present time none of our researches have guided us to form a conclusion that it is a specific infectious disease. Indeed all the evidence contained in this Report is against such a conclusion,
22. The premises upon which we built up such a statement so antagonistic to the theories of HAMILTON WRIGHT are the following:
(a.) There is no evidence of a primary lesion, i.e., a point of invasion of the virus into the body. This however carries with it little weight as many specific infectious disease have a somewhat cryptogenous point of entry
into the buman tissues.
(b.) No specific micro-organisms can be found in any organ or tissue of any case of Beri-beri which can be brought into close causal relationship with the disease. The micro-orgauisms found in WRIGHT's so-called primary gastro duodenitis are to be regarded as ordinary bacteria be- longing to the intestinal flora.
(.) Experimental researches are negative. The blood contains no organisms and the transference of large quantities of Beri-beri blood to the tissues of healtly animals never induces disease.
Similar results are obtainable with the spleen, liver, brain, etc.
When we come to the gastro duo lenal mucosa as found in acute and rapilly fatal cases of Beri-beri and use an emulsion of this for feeding monkeys-animals said by WRIGHT to contract Beri-beri naturally-and obtain uniformly negative results, our faith becomes somewhat shaken in the micro-organismal nature or the specific infectivity of Beri-beri.