The Ascent of Temperatures – Dengue fever reaches Nepal’s Himalayan districts

Due to climate change, Nepal is experiencing a concerning spread of Dengue into mountainous regions where the disease was unknown until a few years ago. In 2025, fourteen of the country’s siteen high-altitude districts reported infections, marking an unprecedented expansion of the virus beyond 2.400 meters above sea level.

A study by Tribhuvan University in Kathmandu confirmed the presence of Aedes aegypti and Aedes albopictus mosquitoes, and their larvae, in the Chandannath municipality, Jumla district, at 2.438 meters above sea level. In Solukhumbu district, no systematic scientific research has yet been conducted, but Dengue cases have been reported in patients without travel history, suggesting the possible presence of vectors in this Himalayan area as well. Until recently, Aedes mosquitoes had only been detected up to 2,100 meters. Over the past two years, however, Dengue has spread across almost the entire country: in 2024, seventy six districts were affected, and in 2025 cases were reported in seventy five of Nepal’s seventy seven administrative areas. According to data from the Epidemiology and Disease Control Division, at least 41.053 people have been infected since January 2024, and eighteen have died.

To better understand changes in vector behavior, scientists from the Nepal Health Research Council (NHRC), in collaboration with the Institute of Tropical Medicine in Antwerp, are collecting mosquitoes from the field and analyzing them to examine their adaptation to new environments, as well as emerging resistance to insecticides. The specimens are carefully observed, photographed, and cataloged, allowing researchers to document patterns of survival, distribution, and resistance. Experts attribute the expansion of Dengue into Nepal’s mountainous regions primarily to global warming, which creates more favorable conditions for mosquito survival and reproduction, even in areas once considered at low or no risk. Increased mobility and

improved road infrastructure have also contributed, facilitating the circulation of the virus across the country. As a result, Dengue is reaching Himalayan communities where healthcare facilities may have limited resources compared to emerging needs.

In these remote and hard-to-access areas, many residents continue to rely on traditional Tibetan medicine, known as Sowa Rigpa, practiced by Amchi, traditional healers who enjoy strong cultural trust and have long served as key healthcare providers within local communities. Practices across the Himalayan region and influenced by Indian Ayurveda and Buddhist philosophy, Sowa Rigpa combines clinical observation, herbal remedies, and a holistic view of health, in which body, mind, environment, and spiritual dimensions are deeply interconnected. The situation represents a growing public health challenge. To curb the spread of Dengue, Nepalese authorities are implementing prevention and awareness strategies, promoting the use of repellents and mosquito nets, proper household environmental management, and community campaigns to eliminate stagnant water and strengthen vector surveillance. The goal is to improve communities’ ability to respond promptly to emerging health threats in a territory increasingly exposed to the impacts of climate change. To date, prevention and vector management remain the primary strategies available to combat Dengue.

Yuri Segalerba was selected from among the applicants for “Earthly Fabulations” online exhibition.