ALGUNS DADOS EPIDEMIOLÓGICOS SÔBRE A MORTALIDADE POR DOENÇAS TRANSMISSÍVEIS RESPIRATÓRIAS AGUDAS NO MUNICÍPIO DE SÃO PAULO (COM UMA CRÍTICA SUCINTA A RESPEITO DA MORBIDADE E DA LETALIDADE)

Abstract

A. GENERAL

1. The epidemiologic features of diseases always present local aspects, according to the epidemiologic structure of each community. Through comparison many factors common to several communities can be pointed out and later the conclusions thus obtained can be generalized, thus establishing the theory or general philosophy of disease which permits one to suggest prophylactic measures. The principal aim of this thesis is to contribute, by the utilization of this method, so as to furnish some information on the epidemiologic features of some diseases in the Municipality of São Paulo, thus enhancing better knowledge of their epidemiology. 2. The Public Health Statistics data and those of the census contain an insufficient number of information on individual characters, as questions regarding ocurrence of disease are very limited as compared with the various features of the population. 3. Mortality data by the various causes of death, usually are the most worthy of confidence, among vital statistics data, the fallacies being limited to variations in clinicai concepts of diseases, gradual improvement in diagnosis, variations in the International Classification of Diseases and Causes of Death and variations in the criteria used for classifying the primary cause of death. 4. Morbidity data have many restrictions, as we all know. However, their study is important because they give an idea on incidence of diseases, especially the benign ones, in which mortality is so low that it does not give us a fair picture of what is going.

B. MORTALITY

1. Official data on mortality are a very good approximation to reality in the Municipality of São Paulo for there are good medicai facilities, clandestine cemeteries are practically non-existent and the rate of deaths through ill-defined and unknown causes is very small, especially since 1930. 2. Mortality through acute communicable respiratory diseases presents a clear trend toward decrease in the Municipality of São Paulo. This fact has been observed in the whole world in greater or lesser degree, and occurs through multiple factors, such as better living conditions, less crowding, evolution of medicine as regards better diagnosis and treatment. 3. Of the diseases studied, the pneumonia group presents the highest mortality, thus becoming a major Public Health problem. However it must be stated that many deaths are classified as caused by pneumonia when this is only a final complication. So, better studies of epidemiology of pneumonia are needed in order to avoid deaths by this group of diseases. 4. Among us the majority of the diseases studied have the highest mortality in the younger age groups, especially from O to 4 years of age. Influenza and pneumonia have higher rates also in the aged. 5. A systematic campaign must be started for immunization against pertussis, diphtheria and small-pox so that the death rates may be rendered lower among us. As these rates are very high during the first year of age and as a great number of deaths occur during the first six months of age and even the first month, immunization should be started in the younger age groups, preferably in children under three months of age, and even newborns. 6. Most of the diseases under study present higher death rates in males than in females, as is usually the case, considering communicable diseases. The exceptions are diphtheria, measles and, especially, pertussis; in the latter disease the death r ate is very much higher in females, which is the rule.7. Our data suggest greater mortality in blacks and half-breeds, followed by whites and yellow in this order. The interpretation is difficult and this study is preliminary. Many factors can alter the rates: the chief one, on ou ropmwn, is the imperfect mode of classifying people regarding race, both in censuses and death certification. 8. The majority of the diseases studied did not present a seasonal variation regarding mortalíty. Although the number of deaths were higher in the colder months, in general, the difference between the number of deaths in these months and the warmer ones was not great.

C. MORBIDITY AND CASE F AT ALITY

1. In the Municipality of São Paulo, case reporting is very defficient, and according to ali indications it is getting worse. It is, therefore, an urgent need to enhance reporting of communicable diseases in our midst. 2. According to official data, morbidity through acute communicable diseases presents in our town a trend toward definite decrease.3. Case fatality regarding reported cases follows the same trend, a fact that probably results in great part from the use of chemotherapic and antibiotic drugs for treating such diseases and thei1 complications.