For many of us, summer is the season of iced lemonade, trips to the beach and never-ending mosquito bites. But where I grew up in Los Angeles, mosquitos — while quite the nuisance — aren’t necessarily something to worry about when I am out late on a hot summer night. But for now, I write this from Oaxaca, Mexico, my home for the next two months, where mosquitos and the illnesses they carry are far worse than a few days of scratching.
A major mosquito-borne illness confronting communities in Oaxaca is dengue, characterized by intense body aches, fever, vomiting and joint pain. Severe cases of dengue can become life-threatening within hours and require immediate medical attention.
According to the Centers for Disease Control and Prevention, 40% of the world’s populations reside in areas that are at risk for transmission, and roughly 400 million people are infected with the dengue virus that results in 21,000 mortalities each year — making it a major global health issue. Epidemiologists even refer to the illness as “the disease of impoverished places” as it is often found in poorer communities of Southeast Asia, the western Pacific islands, Africa and Latin America. Communities with poor housing and infrastructure quality and limited access to waste management, sanitation and potable water are most vulnerable to these increases in dengue infections.
Recently, there has been a rise in cases in areas that have not historically been plagued by dengue, such as in Europe or the United States, and total global cases have increased 30-fold over the last 50 years. Studies have found a correlation between higher environmental temperatures and increased rainfall and a higher incidence of dengue, making climate change a potential reason for a global rise in transmission of mosquito-borne illness.
Climate change exacerbates preexisting inequalities such as lack of access to healthcare, medical resources, education on disease prevention, government preparedness and infrastructure in low-income communities. It can also increase a region’s annual humidity and temperatures and lead to more frequent and extreme natural disasters such as storms and flooding — resulting in stagnant water that acts as a breeding ground suitable for mosquitos.
Where I am living on the coast of Oaxaca, many communities are still recovering from Hurricane Agatha in May, which was the most powerful hurricane to make landfall on the Pacific coast in the last 70 years. Following heavy storms, mosquitos lay eggs inside homes in bathrooms, laundry rooms, trash cans or buckets. Frequent and intense natural disasters leave many of these regions’ government and public health systems unprepared to respond quickly to sudden outbreaks of dengue.
Currently, there are global efforts to provide a vaccine in regions most at risk, along with local initiatives to administer fumigation with fogging machines in city streets, the homes of infected families and drains where mosquito breeding grounds are likely to form. Communities such as those where I live in Oaxaca fumigate the streets every few days and have implemented preventative disease-education campaigns with the slogan “Lava, Tapa, Voltea y Tira,” encouraging people to turn over buckets of water at night. On an individual scale, some people sleep with mosquito nets over their beds or cover their windows and doors and use fans to keep out mosquitos.
UC Berkeley students who are interested in studying abroad in countries with high rates of dengue should research repellents and safe ways to protect themselves from mosquitos, as well as ask their host family how their local government has been responding to the crisis. It’s important to understand the consequences of climate change and global warming, which persistently impact the lowest greenhouse-emitting countries and poorest populations. While abroad, it’s essential to contribute to local efforts toward sustainable tourism and carbon neutrality to minimize your impact on the local environment and greenhouse emissions.