EVALUATION OF THE DIRECT IMPACT OF THE VIDENCE OF THE EL NIÑO AND LA NIÑA PHENOMENA ON THE NOTIFICATIONS OF DENGUE CASE IN THE METROPOLITAN REGION OF CARIRI

Abstract

Dengue is the most common arbovirus in Brazil. The incidence of this disease depends on climatic factors that are products of the relationship between geographic factors specific to each location and atmospheric patterns that can influence the climate of countries and continents. Among these, the El Niño-Southern Oscillation (ENSO) stands out. The present work sought to evaluate the impact of the El Niño and La Niña phenomena on notifications of Dengue cases in the Metropolitan Region of Cariri (RMC). A time series analysis was carried out on confirmed cases of Dengue registered in the municipalities that make up the RMC, available in the Unified Health System database, from 2001 to 2022. To collect information on the El Niño and La Niña index was used using the Oceanic Niño Index (ONI), available from the National Oceanic and Atmospheric Administration. To assess whether the data sets have temporal correlation, the cross-correlation test was used and, in order to determine the existence of a significant difference, the Wilcoxon signed-rank test was applied. The cross-correlation test between the ONI index and the monthly incidence rate of Dengue cases in the RMC indicated a lag of 4 months (r = 0.14, p < 0.05). The Wilcoxon signed-rank test did not identify statistical differences between Dengue records during the El Niño, La Niña and neutral phases. Monthly Dengue cases and the ONI index have a weak correlation. The duration of the climate phenomena El Niño, La Niña and Neutral Phase did not determine a statistically significant change in the pattern of Dengue case records in the study area. This information provides evidence that ENSO has a low or insignificant influence on Dengue notifications in the region considered in this study.