With the recent abundance of major weather events, like Hurricane Helene and Oscar, people are understandably concerned about the destruction and death these events cause. They are right to be worried, especially as climate change is causing larger and more frequent major weather events. But one factor that few consider, which is a cause of many additional deaths, is the environment that the disasters leave behind. Consider for a moment, the bringer of disease, sucker of blood, and climate change-adaptive mosquito.
Mosquitoes love wet, warm, stagnant water, within which they are able to incubate mosquito larvae. These conditions are often left behind after monsoons, hurricanes, or other rainy weather events, extending the impact and duration of the crisis. This is because mosquitos are one of the world’s most prevalent disease carriers. In fact, mosquitoes kill more people every year than any other organism: “Over one million people worldwide die from mosquito-borne diseases every year,” according to the American Mosquito Control Association. These diseases include Malaria, Dengue, Yellow Fever, West Nile Virus, and Zika Virus, just to name a few. As mosquito populations grow, so does the risk of contracting these debilitating diseases.
In the aftermath of hurricanes, mosquito populations flourish. In the wake of Hurricane Helene, the Center for Disease Control (CDC) has posted warnings about heightened mosquito populations. One notice says: “Increased rainfall due to Hurricane Helene may result in increased mosquito populations. In areas with ongoing spread of mosquito-borne diseases, such as dengue or West Nile virus, you may be at increased risk of getting infected from mosquito bites.”
These extreme weather events are only forecast to become worse in scope and more frequent. A large part of this is due to global warming impacting the El Niño and La Nina systems as well as the severity of monsoons, which can affect the rate of precipitation and severity of floods in various regions. The Earth and Environmental System Modeling from the United States Department of Energy has stated that “A new study has found that global warming is impacting the relationship between El Niño-Southern Oscillation (ENSO) and monsoon precipitation in Asia and Australia. Aided by tree-ring climate data, this study showed that the relationship between ENSO and monsoon precipitation has been enhanced since the late 20th century, with the influence of anthropogenic climate warming being a significant factor. This effect could lead to more frequent and severe monsoon extremes, resulting in devastating floods and droughts in the monsoonal regions.”
So, why are mosquitoes such a prevalent problem, and why are they an ever increasing threat? Well, part of that is due to climate change, or humanity’s impact on the environment. Many factors from humans have created perfect conditions for the deadly insects: climate change, loss of biodiversity, deforestation, temperature increases and weather pattern changes increase the amount of areas with still water (which trees typically prevent), and reduce the amount of predators that can limit mosquito populations. These factors help create more habitats that mosquitoes can thrive in, and they have expanded the area in which the mosquitoes can live, putting more people at risk than ever before. Regions with cold and dry climates are typically mosquito-free, but in the wake of climate change and extreme weather conditions, these regions’ climates are changing, causing an increase in mosquito populations.
Mosquitoes are perhaps the most significant spreaders of diseases among people, threatening a potential 1.4 billion people with just three of the many diseases that they spread being dengue, chikungunya, and malaria, according to the World Health Organization (WHO). This leads to a concerning correlation between human activity and mosquitoes: as human based climate change and alteration of the natural world grows, so too does the reach and effect of mosquitoes, which are more suited for the new environment than almost any other animal.
So what can people do about this growing threat? Two potential strategies include personal protection and reduction of the standing water that mosquitos grow in. In a CDC announcement following the recent Hurricane Helene, the organization recommended wearing long sleeved shirts and pants and using more effective bug repellents for protection. They also recommend removing standing water near your home if possible. The WHO elaborates on possible mosquito habitation areas: gutters, uneven concrete, potted plants, and spare or discarded tires are possible yet sometimes overlooked collectors of standing water. As mosquito larvae only need one inch of water to fully grow, diligence and awareness are important for preventing the spread of mosquito-borne diseases.
To many people, mosquitoes are simply small and annoying, but with growing major weather events, they can quickly become a large and possibly deadly threat. They are an advancing issue that more than ever needs to be looked out for, and cared for in the wake of devastation. Looking forward, we must educate ourselves and others about the less-seen effects of climate change like this one, and work towards prevention of further extreme circumstances.
Sources:
American Mosquito Control Association “Vector-borne Diseases”, American Mosquito Control Association https://www.mosquito.org/vector-borne-diseases/.
Centers for Disease Control and Prevention. (n.d.). Mosquito-borne diseases: Response to outbreaks. Centers for Disease Control and Prevention. https://www.cdc.gov/mosquitoes/response/index.html.
Jackson, Alex. “Explainer: How Climate Change Is Amplifying Mosquito-Borne Diseases World Mosquito Program.” World Mosquito Program, World Mosquito Program, www.worldmosquitoprogram.org/en/news-stories/stories/explainer-how-climate-change-amplifying-mosquito-borne-diseases.
NETEC. “Situation Report: Mosquito-Borne Illnesses” NETEC, August 28, 2023 https://netec.org/2023/08/28/situation-report-mosquito-borne-illnesses/.
Singh, Poonam Khetrapal. “Towards a Mosquito-Free Monsoon.” World Health Organization, World Health Organization, 25 Aug. 2016, www.who.int/southeastasia/news/opinion-editorials/detail/towards-a-mosquito-free-monsoon.
World Health Organization. Vector-borne diseases. World Health Organization. 24 September 2024 https://www.who.int/news-room/fact-sheets/detail/vector-borne-diseases.
Xu, Chenxi, S.-Y. Simon Wang, Krishna Borhara, et. al “Global Warming is Linked to Monsoon Precipitation Extremes”Earth and Environmental System Modeling, United States Environmental Protection Agency, 18 February 2023. https://climatemodeling.science.energy.gov/research-highlights/global-warming-linked-monsoon-precipitation-extremes.