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In recent years, we've witnessed a troubling trend: dengue fever is on the rise, and climate change is playing a significant role in its spread. Higher temperatures speed up the virus's development inside mosquitoes, shortening the time it takes for a mosquito to become infectious after biting an infected person [1,2]. Increasing rainfall results in the gathering of water and the creation of puddles in open spaces, which in turn provides perfect conditions for mosquito populations to multiply.The consequences of these climate-driven changes are being felt worldwide. Regions that once saw only occasional dengue cases are now experiencing regular outbreaks. Meanwhile, areas where dengue was already endemic are seeing more intense and frequent epidemics.In South America, dengue incidence has surged over the past two decades. This increase correlates with rising temperatures and more days with optimal conditions for dengue transmission. One example is Brazil which has seen a continuous transmission of dengue since 1986, with high incidence rates correlating with elevated temperatures and precipitation volumes [3].&nbsp;The El Niño phenomenon, characterized by abnormal warming of Pacific Ocean waters, has also been associated with increased dengue outbreaks in coastal regions of Peru and Ecuador, where the climatic conditions favor the mosquito's habitat and breeding sites [4]. In Colombia, unusually high temperatures during El Niño years have been shown to significantly increase dengue cases, with temperature having a more substantial impact than precipitation [5].Dengue cases have also experienced a significant upswing across the Asian region. In Bangladesh, a surge in dengue fever cases has been associated with elevated temperatures and increased precipitation. The most pronounced rise in cases is noted when the mean temperatures hover between 28°C and 30°C [6]. In Malaysia, climate factors such as temperature, rainfall, humidity, and wind speed have been statistically linked to dengue incidence, with wind speed showing the most significant impact [7]. In Yogyakarta, Indonesia, fluctuations in rainfall, air temperature, and humidity significantly affect dengue cases, highlighting the intricate interplay between various climatic factors and dengue transmission.The complex and region-specific nature of the climate-dengue relationship is seen in the United States where the impact of rising temperatures on dengue transmission varies by region. Cities like Los Angeles and Houston are experiencing increased dengue risk due to warming temperatures. However, in cities like Miami, Brownsville, and Phoenix, extreme heat has paradoxically reduced the risk of dengue.&nbsp;The relationship between temperature and dengue is context-dependent, with positive correlations observed at intermediate temperatures around 24°C, especially in areas with high-temperature variation and population density [8]. Rainfall, while not always directly correlated with dengue cases, can create breeding sites for mosquitoes, particularly in urban areas with inadequate infrastructure and water storage practices, as seen in Espírito Santo and other Brazilian cities [3,9].The rise of dengue fever is a stark reminder of the profound impact climate change has on public health. As temperatures soar and rainfall patterns shift, the breeding grounds for Aedes mosquitoes expand, leading to increased dengue transmission worldwide.The interplay between higher temperatures and unusual rainfall patterns necessitates targeted public health interventions and early warning systems. Understanding these climate-driven changes is crucial for preparing and responding to the escalating threat of dengue fever.Climate change is reshaping the infectious disease landscape, with dengue fever as a prime example. Warmer temperatures and erratic rainfall patterns are the perfect storm for mosquito breeding. As we navigate through this warming and increasingly wet world, our resilience will be tested, but with proactive measures and adaptive strategies, we can protect our communities from dengue’s escalating threat.References [1] Mercier A, Obadia T, Carraretto D. et al. Impact of temperature on dengue and chikungunya transmission by the mosquito Aedes albopictus. Sci Rep 12, 6973 (2022). https://doi.org/10.1038/s41598-022-10977-4.&nbsp;[2] Dengue | CDC Yellow Book 2024[3] Denise M, Poton Edinaldo da S, Santos Gustavo R, Vieira, Jéssica dos S, Nery Laís A, G, Ramalho, Cátia Oliveira de, Paula Morais. A influência das variáveis climatológicas nos casos de dengue em municípios do espírito santo. undefined (2018). doi: 10.17648/INTELLETTO-2525-9075-V2-N3-04[4] Cristian Díaz-Vélez, Jorge Luis Fernández-Mogollón, John A Cabrera-Enríquez, Stalin Tello-Vera, Oscar Medrano-Velásquez, Elmer Córdova-Calle. Situation of Dengue after the Phenomenon of the Coastal El Niño. undefined (2020). doi: 10.5772/INTECHOPEN.92095[5] Adriana Lorena, Sanchez, Nazly E, Sánchez, Andrés Mauricio, Gómez Sánchez. Climatic phenomenon and meteorological variables influencing the dengue fever incidence in Colombian South Pacific region: Modeling study. Annals of Tropical Medicine and Public Health, undefined (2017). doi: 10.4103/ATMPH.ATMPH_395_17[6] Mohammad Nayeem Hasan, Ibrahim Khalil, Muhammad Abdul Baker Chowdhury, Mahbubur Rahman, Md Asaduzzaman, Masum Billah, Laila Arjuman Banu, Mahbub-Ul Alam, Atik Ahsan, Tieble Traore, Md Jamal Uddin, Roberto Galizi, Ilaria Russo, Alimuddin Zumla, Najmul Haider, Two decades of endemic dengue in Bangladesh (2000–2022): trends, seasonality, and impact of temperature and rainfall patterns on transmission dynamics, Journal of Medical Entomology, Volume 61, Issue 2, March 2024, Pages 345–353, https://doi.org/10.1093/jme/tjae001[7] Childs ML, Lyberger K, Harris M, Burke M, Mordecai EA. Climate warming is expanding dengue burden in the Americas and Asia. medRxiv [Preprint]. 2024 Jan 9:2024.01.08.24301015. doi: 10.1101/2024.01.08.24301015. PMID: 38260629; PMCID: PMC10802639.[8] Devin Kirk, Samantha Straus, Marissa L, Childs Mallory J, Harris Lisa I, Couper T, Jonathan Davies, Coreen Forbes, Alyssa-Lois M, Gehman Maya L, Groner Christopher, D G Harley, Kevin D, Lafferty, Van M, Savage, Eloise B, Skinner, Mary I, O'Connor Erin A, Mordecai. Temperature impacts on dengue incidence are nonlinear and mediated by climatic and socioeconomic factors. bioRxiv, undefined (2022). doi: 10.1101/2022.06.15.496305.[9] Carolina, Cristina, Bicalho., Iraziet, da, Cunha. The influence of climatic factors on dengue epidemies in the cities cuiab a (mato grosso state) and lavras (minas gerais state), brazil, using statistical methods. undefined (2013).

Dengue in a Warming and Increasingly Wet World: When Higher Temps and Unusual Rainfall Mean Higher Dengue Risk

As the mercury rises, so does the risk to our health. It’s not just about the discomfort; extreme heat waves are a silent predator, particularly menacing for expectant mothers and their unborn children. The scorching temperatures have been linked to a spike in complications like pre-eclampsia and gestational diabetes, not to mention the threat of low birth weight or even stillbirth.But the danger doesn’t stop at birth. Our brains and bodies struggle under the oppressive heat, with studies revealing a worrying trend of cognitive decline and a surge in workplace accidents, especially for those braving the elements in outdoor jobs. And it’s the most unexpected victims—women, the elderly, and even the higher earners—who find themselves at the mercy of the heat [1,2].The relentless heat doesn’t just beat down on us; it puts a strain on our healthcare systems too. As temperatures climb, so do cases of heat-related illnesses, chronic conditions, and injuries. With climate change turning up the dial, we’re seeing an alarming rise in heat-related deaths, underscoring the urgent need for robust, climate-adaptive healthcare strategies.In the heart of the heatwave, our cardiovascular health is on the frontline. Every additional day of blistering heat is not just uncomfortable—it’s deadly, contributing to a staggering number of heart-related fatalities. The elderly and those with pre-existing heart conditions are in the crosshairs, facing the brunt of this thermal assault.The long-term effects are just as harrowing. Our hearts are under siege, battling against the heat-induced stress that can reshape and damage this vital organ. When heat combines with exercise and humidity, it’s a perfect storm for cardiac distress, potentially leading to serious conditions like myocardial ischemia, especially for those already living with heart disease [3,4].So, what can we do? Understanding our body’s response to heat is the first step in protecting our heart health and developing strategies to shield those most vulnerable from the heat’s hidden dangers. Stay cool, stay informed, and stay prepared as we navigate the scorching path ahead.References[1] "Heat and Worker Health." undefined (2023). doi: 10.48550/arxiv.2301.11554.&nbsp;[2] Andrew, Ireland., David, W., Johnston., Rachel, Knott. "Heat and Worker Health." undefined (2023).[3] Andrio, J., R., dos, Santos. "Heat and the Heart." Yale Journal of Biology and Medicine, undefined (2023). doi: 10.59249/hgal4894.[4] Yash, Desai., Haitham, Khraishah., Barrak, Alahmad. "Heat and the Heart." Yale Journal of Biology and Medicine, undefined (2023). doi: 10.59249/HGAL4894.

Feeling the Burn: How Extreme Heat is Taking a Toll on Our Health

Climawahealth

ClimawaHealth is an independent consultancy firm committed to pioneering research that advances our understanding of health economic impacts of climate-water-related events.  Our focus encompasses the intricate interplay of hydrological and climatic factors within the broader scope of global development. Our mission: to empower policymakers, health systems, and front-line caregivers with rigorous science, real-world evidence, and economic analysis. We believe true resilience arises when health, economics, and the environment align.

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Dengue in a Warming and Increasingly Wet World: When High...

Feeling the Burn: How Extreme Heat is Taking a Toll on Ou...