O ritmo climático e incidência da dengue na cidade de Porto Alegre/RS – uma análise de dezembro de 2014 a abril de 2016

Abstract

Recent studies have pointed out that Aedes aegypti is adapting to adverse climatic conditions, but in the most southern latitudes of Brazil, for now, autochthonous dengue cases have a more seasonal behavior. They increase in the time conditions most favorable to vector development (prevalence of minimum and maximum temperature between 22 ° C and 30 ° C with regular but intermittent rainfall), usually between December and April, and decrease when it becomes colder and unfavorable to development of the vector. In addition, the total numbers vary greatly from year to year and the frequency of occurrences is variable even over the most favorable period. This variability is related to the reintroduction of the virus or its new serotypes, and to the degree of sanitary surveillance by both the public power and the population. It is also assumed that there may also be a relationship with the annual climatic variability and with the greater or lesser participation of one or other atmospheric system and with the types of weather that result from them. Thus, this work deals with the investigation of annual and monthly climatic variability for the period of the most conducive year to the proliferation of viral diseases transmitted by the Aedes aegypti mosquito, in Porto Alegre / RS, in the years 2014/2015 and 2015/2016, and also about the analysis result of the kinds of weather that have happened in these months. For the defined temporal limits, monthly meteorological data were compared to standard climatological and related to El Niño-Southern Oscillation anomalies. In addition, daily data of climatic elements as well as synoptic charts were used to define the performance of atmospheric systems and kinds of weather.This work also presents the classification process of the climatic potential of the Aedes aegypti mosquito proliferation to Porto Alegre / RS, using the SACDENGUE method and its results per epidemiological week. These data are confronted with the confirmed cases of dengue recorded by the Sanitary Surveillance of Porto. As a result, there were clear differences between summer 2014/2015 and summer 2015/2016 in averages and monthly totals, in global anomalies, and also in the participation of atmospheric systems and kinds of weather, which may have corroborated to the differential occurrence of dengue from one year to the next.