VIRUS CARRIERS

VIRUS CARRIERS

388 THE BLOOD ALCOHOL TEST they may have a selective action on the M. leprce. Unfortunately early hopes have not been fully justified. G. R. Rao in ...

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388

THE BLOOD ALCOHOL TEST

they may have a selective action on the M. leprce. Unfortunately early hopes have not been fully justified. G. R. Rao in India reported4 that the dyes had no appreciable effect either on the course of the disease or on the causative organism. R. G. Cochrane found5 that intradermal injections of brilliant green had little effect on the bacilli in the lesion, although there was some flattening of infiltrations and nodules. French clinicians in Indo-China have recently been giving 1 per cent. methylene-blue in double distilled water intravenously in doses as large as 20 c.cm., and regard this drug as having a specific action in leprosy.6 Unpleasant reactions were avoided by extreme attention to purity and sterility. While the results are encouraging, it must not be forgotten that so many remedies in leprosy have only been effective in their inventors’ hands. One difficulty in assessing treatment is that many of the lepra bacilli found in the body are already dead ; no drug would be efficacious unless it actually caused their disintegration. On the other hand, there is evidence that M. leprce will live for some years under laboratory conditions in biopsied material without apparent change and remaining acid-fast. The next step should be an endeavour to find out whether injections of methyleneblue combined with hydnocarpus preparations are more efficacious than other lines of treatment. The claim that this treatment will rapidly render open cases non-infectious will be looked upon with caution, for, in the general experience of leprosy workers, the more dramatic the improvement the less permanent the results. VIRUS CARRIERS IN the control of epidemic disease of bacterial such as cholera, diphtheria, enterica, and " cerebro-spinal fever, the identification of carriers has proved of help and it is pertinent to inquire whether virus infections may spread in a similar way. To what extent true carriers of poliomyelitis and encephalitis exist it is not yet possible to say, as although their virus has been isolated, no simple laboratory test for their detection is available. It would seem probable, however, that the most common transmitter of infection is not a true carrier but a person suffering from an unrecognised attack. The true nature of such an attack may be suspected when a mild febrile illness occurs in the midst of an epidemic outbreak, but as it does not present any characteristic clinical features or provide any reaction capable of laboratory investigation, such suspicion may or may not be correct. In the absence of an epidemic such an attack is not only unrecognised but unrecognisable. It seems that in some virus infections there may be persons affected, and therefore possible infection sources of spread, in whom the initial at all. is no This produces symptoms certainly true as regards encephalitis of Economo type. As the result of the great epidemic of 1924 a number of young people in this country are suffering from typical post-encephalitic phenomena of various kinds in whom after the fullest inquiry no history can be obtained of a single day’s illness, or of any sign or symptom which could be construed as the initial infection. Such " occult " infections in epidemic encephalitis, which form quite a distinct group from the unrecognised or the abortive attacks, may prove as serious in their after-effects as a full-blown primary attack. There are no late manifestations after polio-

’ origin,

"

4 Leprosy Rev., 1935, vi., 4. Internat. Jour. of Leprosy, 1933, i., 495. Freville, L. H. F. : Bull. de la soc. méd.-chir. de l’indochiue, 5

6

1934, xii., 615.

to those following encephalitis of Economo type and similar retrospective deductions are not possible ; but there are other grounds for thinking that in poliomyelitis also cases do occur which merit the term occult. Levaditi1 gives his reasons for thinking that this type of poliomyelitis is important in spreading the disease. Virus recovered from rhinopharyngeal and gastro-intestinal sites may be the only evidence of attacks which are not merely abortive but " tota,lement inapparentes." Such a view is supported not only by the wide divergence between the small percentage of paralytic cases in the course of one epidemic, but also by the apparent immunity of almost the whole population in the affected area. Experimentally the virus has been obtained not only from the throat but also from the intestinal contents of those affected. Monkeys can be infected not only by the nasopharynx but by introducing the virus into the stomach, and even into a loop of It is possible that the primary site of intestine. human infection may be either rhino-pharyngeal or gastro-intestinal ; a sore-throat or a gastric disturbance may be its only signs of infection.

myelitis comparable

THE BLOOD ALCOHOL TEST ESTIMATION of the alcohol content of the blood has been suggested as a means of establishing the extent to which a person is under the influence of drink. Reliable evidence on this point would often have judicial value. Apart from the question of whether a suspected motorist is unfit to drive by reason of drink, it would assist justice to know the extent to which an injured pedestrian was himself drunk. Inebriation is in some circumstances a defence against a criminal charge, and there are several methods, notably that of Widmark, of accurately estimating the concentration of alcohol in the blood. But even when this figure is known its practical value is questioned. Dr. Ernst Silberstern has satisfied himself2 from experience as chief police surgeon in Vienna that the quantity of alcohol in the blood does not correspond with the condition of the drinker. Many factors modify the effect of alcohol, e.g., the form of drink, the relation to food, the stimulants that have been taken after the alcohol, accessory factors such as tobacco, carbon monoxide, climate, and psychological constitution. The capacity of the person for doing a particular act, or the degree of his responsibility for his acts, is, he thinks, more likely to be estimated correctly by an experienced clinician. Subject to these limitations however Dr. Silberstern finds that the blood alcohol test has definite uses. A negative result may prove that the subject has taken no drink at all-a finding of importance in certain motor cases. It may also serve to fill up gaps in the clinical evidence, and to amplify the clinical findings and explain their relationship to the general condition. When it is not possible to make a clinical examination at once, an immediate sample of blood may have a peculiar Since in this country the sample can only value. be taken with consent, the test may take long to Nevertheless there must be come into general use. cases in which a solicitor or a medical man acting on behalf of an accused motorist should suggest an If it were negative or the immediate blood test. amount of alcohol very small the result would be a If the finding were strong point in his favour. unfavourable, the advisers of the accused would not 1 Levaditi, J.: Caractère inapparent de épidémique, Paris Méd., Jan. 12th, 1935. 2 Wien. klin. Woch., 1934, xlvii.,

la 1518.

poliomyelite