Report of the Medical Officer of Health, Cairo City.

  • Egypt. Cairo City Health Inspectorate.
Date:
[1916]
Catalogue details

Licence: Public Domain Mark

Credit: Report of the Medical Officer of Health, Cairo City. Source: Wellcome Collection.

    24/186 (page 16)
    In Table XI are shown the numbers of cases and deaths, in 1915, of each of the eight diseases forming the zymotic group under consideration in comparison with the expectation of cases based on the ratios of deaths to cases recorded in the three preceding years. Now the most prominent feature of this table is the extraordinary discrepancy between the number of cases of typhoid actually recorded and the anticipations, based on the 1914 ratio of deaths to cases in that year, and in considering the extent to which the zymotic deaths in 1915 can be accepted as a basis for a comparison of incidence with other years, it will serve the purpose to confine our attention primarily to the position as regards this disease. Excluding other influences, such as increased virulence, of which no evidence existed, the most obvious explanation of the discrepancy between the 2,378 cases of typhoid fever actually recorded in 1915, and the expectations from the number of deaths in that year of 4,585 cases, based on the ratio of deaths to cases recorded in 1914, might seem to lie between a lessened discovery of cases in 1915 in consequence of some diminution in the efficiency of control, and an increased recording of deaths as a result of improved diagnosis of the causes of these. In weighing these alternatives, it is impossible to give any definite data upon which to base logical proof, but a consideration of all the circumstances points to the latter as the true explanation, and implies in consequence an unreliability of the death figures for this year as a basis for zymotic comparison. Thus we have the actual fact that, in 1915, on account of the extensive outbreak of the typhoid-like fever already referred to, and of the vernal prevalence of typhoid fever, the stringency of control was, coincident with the period of the greatest typhoid prevalence, actually increased. Not only were the usual inquiries made, but a house-to-house search for concealed cases was instituted in addition whenever the discovery of a fresh outbreak in a lower-class district led to a suspicion of the likelihood of the existence of these. To seek an explanation of the discrepancy therefore in the direction of lessened efficiency ■of control would be scarcely justified by the circumstances. On the other hand, in the present instance we were dealing with a disease of a nature such as has just been described as presenting no obvious external post-mortem appearances, and therefore one in which the possibility of a missed diagnosis is most likely to occur when this falls to be made from a mere inspection of the body after death. In this disease, therefore, more than in almost any other, any increased discovery of living cases is likely to lead to an increase in the number of recorded deaths, inasmuch as every fatal case of the disease previously recognized during life is a case from which the possibility of diagnostic error after death has been removed. It would be difficult at any time to assess with accuracy the extent to which this influence increased recorded deaths, but in the year in question, as will be subsequently more fully described, the typhoid figures were so mixed up with those of the resembling fever already referred to as to make it impossible to appraise, with ;any exactitude, the number of fatal cases of the former disease discovered during life. Under the circumstances, therefore, the death returns for the disease in question must be considered as so open to external influence as to render any comparison on a numerical basis impossible, and it may be taken that the influence exerted by the increased control of infectious disease has, in 1915, so modified not only the recorded incidence, but also the death returns of this as well as other diseases in the zymotic group, as to render their acceptance as a basis for zymotic comparison inadmissible. Under these circumstances therefore the only conception of the probable relative prevalence of the various zymotic diseases in 1915, as compared with previous years, is to be derived from impressions obtained in dealing with them. This is obviously a highly unscientific basis upon which to build any estimate of com¬ parative incidence, but in a country such as this, where the ordinary statistical methods themselves provide an extremely inaccurate means of comparison, the impressions of any person in close association with the work of controlling infectious disease acquire a value which under other circumstances they would not possess. I propose, therefore, in the absence of any possibility of a statistical comparison, to put these impressions on record for what they are worth. As regards the eight principal infectious diseases, the idea of increased prevalence only arose in the case of three of these. These were typhoid, typhus, and relapsing fevers. In the case of the first of these there was undoubtedly increased incidence due to an epidemic which occurred in the spring.