Mortality Patterns of Influenza and Pneumonia in the Macroregion of Central Mexico: An Analysis of Its Trends and Its Geographic and Climatic Distribution

Abstract

This work focuses the macro-region of Central Mexico to investigate two aspects of the mortality by influenza and pneumonia in Central Mexico: (i) its recent trends (1979-2015), and (ii) its geographic and climatic distribution. The study analyzed monthly municipal reports of mortality from the National Archive of Health Information (SINAIS), population data from four National Census, monthly temperature (T), and humidity (ed) data, from the Climate Research Unit of the University of East Anglia (CRU-TS4.01). With respect to (i), results show that, despite a large population increase (of 80%), mortality rate decreased significantly (60%). With respect to (ii), results indicate that the largest mortality by influenza and pneumonia occurs mainly in two cold and dry regions (T < 16 °C and Tmin and ed < 10 hPa): over the Central Mexican Plateau and the region formed by the leeward sides of the Sierra Madre Occidental and the Sierra Madre Oriental. This climate-mortality relation explains average geographic distributions, but not anomalous patterns; mortality trends, therefore, cannot be explain in terms of climate trends. Likewise, such relation cannot explain mortality over the largely populated megacities of Mexico City, Guadalajara y Puebla; the mortality over these cities is significantly lower than that of the domain average. Both exceptions suggest that, a more complete explanation of the causes shaping the spatial patterns of mortality, such explanation would need to include non-climatic factors, such as biologic, socioeconomic or cultural factors.