Climate Variability: Precipitation as a Study Parameter for Dengue Cases in the Coast, Wilderness, Mountain Range and South Cearense Between 2007 and 2019

Abstract

Dengue has become one of the main public health problems in the tropical world, especially in countries with socioeconomic precariousness. Thus, the general objective of this research is to analyze and compare the cases of dengue with precipitation and the associated phenomena in four cities in the State of Ceará (Brazil): Aquiraz, Boa Viagem, Viçosa do Ceará and Brejo Santo, in which they represent environments geographic regions (coast, backlands, mountain range and south of Ceará) between the years 2007 and 2019. For this, a survey of statistical and geographical data was carried out through Datasus, Funceme, IBGE, IPECE, as well as a descriptive survey of dengue cases municipalities in the region, presenting their social, economic, environmental and, mainly, pluviometric data. Associated with this information, research was carried out on the influence of physical mechanisms and atmospheric systems that influence rainfall and climatic conditions in the northeast region of Brazil (NEB), such as: anomalies of the Sea Surface Temperature (TSM) and the establishment of a year -standards using the quantile technique based on rainfall over the past 30 years (1990-2019). Finally, the data of precipitation and notifications of Dengue cases were inserted in the Holt-Winters modeling in the R software, as it was perceived to be the most applied to the seasonal and trend data observed throughout the research. This action aimed to predict the precipitations and cases of the disease for the next 24 months, in order to subsidize government and civil actions for planning to combat Dengue. The results obtained in the research highlighted that in the drier years the cities of Boa Viagem, Viçosa do Ceará and Brejo Santo registered a higher occurrence of Dengue cases; for Aquiraz (a coastal city), the years with rainfall close to the climatological normal presented more cases of the disease. The municipality that recorded the highest rainfall in the survey period was Viçosa do Ceará (highest altitude), which also had fewer cases of Dengue. The city with the lowest rainfall was Boa Viagem (central backlands of Ceará). Brejo Santo (greater latitude, southern Ceará) presented more occurrences of Dengue cases in the period from 2007 to 2019. Therefore, it was observed that the peaks of the disease in the municipalities were registered more frequently in low rainy years, except in Aquiraz where it was increase in cases in years with rainfall close to climatology. Regarding the results of the modeling, these were considered satisfactory, taking into account the trends and seasonality, to predict the amount, mainly, of precipitation.

Keywords
precipitation; dengue; climatology; health; Holt-Winters