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During Brazilian summers, there is traditionally concern about arboviruses. However, in the last years of the past decade, specifically during the periods of 2015/2016 and 2023/2024, this concern was exacerbated by the strong El Niño phenomenon. The interaction between rising temperatures and the occurrence of intense rainfall, typical characteristics of El Niño, contribute to heightened activity of Aedes aegypti, the vector of arboviruses, which tends to seek more human blood in environments with higher temperatures. The possibility of an epidemic becomes even more alarming in these El Niño conditions, exacerbating concerns about public health. The goal of this study is to conduct a review of data and literature on arboviruses and their occurrences in Brazil over the last decade, focusing on epidemics of dengue, Zika, and chikungunya, and their correlation with periods of strong El Niño occurred in 2015/2016 and 2023/2024. The research investigates how climatic changes (increased rainfall and heat) during strong El Niño affect the role of the Aedes aegypti mosquito, the main vector of arboviruses in Brazil. Additionally, it analyzes the relationship between arbovirus epidemics and socio-environmental factors such as urbanization, population density, and sanitation conditions, as the mosquito is urban and lives inside human households. The methodology employed focused on analyzing the major arbovirus epidemics documented in Brazil, particularly in Rio de Janeiro, over the past decade, alongside an examination of the incidence of the strong El Niño climatic phenomenon. This research utilized data sourced from various repositories, including GLOBE, GLOBE Observer, the Global Mosquito Observations Dashboard (mosquitodashboard.org), epidemiological bulletins from Rio de Janeiro, Ministry of Health reports, and the LIRAA (Rapid Index Survey for Aedes aegypti), IBGE, INMET, CLIMATEMPO, NOAA and others. Our analysis has shown that several vulnerabilities make Brazil, with a focus on Rio de Janeiro city, particularly susceptible to the multifaceted impacts of climate change. Notably, outbreaks of arboviruses such as the Zika and Dengue fever epidemic in 2015/2016 and the Dengue fever outbreak in 2023/2024 in Brazil have been partially attributed to the prevailing of strong El Niño conditions during those years. Aedes aegypti, as the primary vector of Zika and dengue, exhibits a preference for hot and humid climates as arose in extreme events during strong El Niño. Our conclusions indicate that extreme events associated with the strong El Niño phenomenon, as experienced in 2015/2016 and 2023/2024, contribute to heightened infestations of Aedes aegypti and the epidemic of dengue cases in Brazil. Aedes aegypti exhibits increased reproduction rates and longevity in higher temperatures, leading to amplified proliferation, as evidenced by the collected data.