A report on hemoglobinuric fever in the Canal Zone : a study of its etiology and treatment / by W.E. Deeks and W.M. James.

  • Deeks, W.E.
Date:
1911
Catalogue details

Licence: In copyright

Credit: A report on hemoglobinuric fever in the Canal Zone : a study of its etiology and treatment / by W.E. Deeks and W.M. James. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

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    shown in Table III, should be kept carefully in mind in examining Chart No. 2. TABLE III.—Showing the annual average of the total number of employees of the Commission per year; the number of admissions due to malaria per thousand of this annual average to all Commission hospitals; thevarious annual percentages of the maximum rate per thousand of admissions, which maximum occurred in 1906; the tiumber of admissions due to malaria per thousand of the annual average to Ancon Hospital, and the percentage of these admissions of the total malarial admissions. Year Average num- ber of employees per year. Number of ad- missions per thousand per year, due to malaria, into all hospitals. Per cent per year of the 1906 maximum of admissions per thousand in all hospitals. Number of ad- missions per thousand per year, due to malaria, into Ancon Hospital Per cent of the total number of cases of malaria, per thousand em- ployees per year, admitted to Ancon Hospital. 1905 13,331 514 61 339 65 1906 26,500 821 100 285 34.7 1907 39,343 424 52 165 40 1908 43,890 282 34 186 66 1909 47,167 215 26 187 87 We have not added to the figures and curves in Chart No. 2 the difference between the number of cases of malaria admitted to Ancon Hospital and the total number of cases of malaria, in order to show graphically the variation of the malaria rate for the Canal Zone; because a larger percentage of malarial cases is admitted to Ancon Hospital when the malaria rate is high than when it is low: for example, in 1907, 40 per cent of the malarial cases in the Zone hospitals was admitted to Ancon; but it is probable that a lower percentage than 40 was admitted in March, April, and May, and a higher in July, August, September, and October. Chart No. 2, and Tables H and HI, show that since 1906 malaria has steadily declined in prevalence. A well marked seasonal variation is plainly evident. This variation is somewhat exaggerated by the increased percentage of admissions when the malarial rate for the Zone is high, and the decreased percentage when the rate is low. The seasonal variations correspond exactly to the duration of the wet and of the dry seasons, the curve being high in the former and low in the latter. This seasonal variation is due in a very great degree to the fluctua- tions in the amount of estivo-autumnal malaria. The difference between the curve of the total malaria and that of positive cases, in Chart No. 2, represents the amount of clinical malaria. At least 80 per cent of this clinical malaria is estivo-autumnal, and if this 80 per cent were added to the curve representing the prevalence of estivo-autumnal malaria shown by the positive blood examinations, the seasonal variation in this kind of malaria would be much more evident than the chart indicates. Even if the positive cases only are