KATHMANDU, JUNE 5
Nochaya Maya (85), a resident of Chandragiri-5 on the western outskirts of Kathmandu, is recovering from dengue fever. Reflecting on her experience, she remarked, "I had never seen mosquitoes in Kathmandu a decade ago, but now I am suffering from a disease transmitted by their bites."
Dengue is a viral disease transmitted by female Aedes aegypti and Aedes albopictus mosquitoes. The same vectors also transmit Chikungunya, yellow fever, and Zika virus, according to the World Health Organization.
"I cannot recall mosquitoes being present in the past decade, but now it's getting hotter than ever before. We never used fans or air conditioners, but that has completely changed now," she continued. "The environment used to be pristine-clean air, water, and atmosphere, biodiversity. Now, all of that seems like just a dream."
Shrestha mentioned that she had never been to a hospital for any ailment before. Reflecting on her struggle with dengue fever, she said, "It was really tough since there was no definite medicine for it. Thankfully, it didn't take my life."
"We are now experiencing extreme temperatures, drought, irregular rainfall, and air pollution, without knowing the cause behind it," she added.
With the recent rise in global temperatures, Nepal is among several nations severly impacted by climate change.
Even Prime Minister Pushpa Kamal Dahal, referring to the UN Secretary-General Antonio Guterres' visit to the Everest Base Camp in the autumn of last year, emphasised Nepal's burden of climate change, for which it bears no responsibility, at the International Expert Dialogue on Mountains, People, and Climate in Kathmandu.
Although Nepal is not a major contributor to global warming, it has borne the brunt of its effects, including adverse impacts on melting glaciers that pose significant risks to downstream areas, loss of biodiversity, an increase in invasive alien species, vector-borne disease, drought, heat-wave and mental health issues.
Shrestha also observed the presence of Kade banmara, scientifically known as Lantana Camara, an alien invasive plant species, in and around Chandragiri-something she had not encountered in the previous decade.
Attributed to climate change, Nepal has witnessed an unprecedented rise in dengue cases, a vector-borne disease, across all 77 districts, including the higher hilly and Himalayan regions, as well as the Kathmandu valley, which was considered unaffected by dengue a decade ago.
How does climate change fuel vector-borne diseases
Climate change influences precipitation patterns by altering atmospheric moisture content, weather system, storm characteristics, and seasonal cycles, leading to diverse and region-specific changes in precipitation, said Dr Jagadish Parajuli, a climate public finance specialist at Asian Disaster Preparedness Centre.
He further stated that two aspects of climate change-increasing temperature and decreasing precipitation-are often interconnected. Rising temperatures can influence precipitation patterns, leading to a reduction in the amount of rainfall or snowfall in a particular area.
Dr. Yadav Joshi, an environmental health expert, said the unwanted collection of water brought by rainfall after drought creates a breeding environment for dengue mosquitoes, posing a health risk to nearby human settlements. Dengue mosquitoes need stagnant water to breed and lay their eggs.
Shrestha also shared her observations, noting that amidst rising temperatures, mosquitoes have become prevalent everywhere due to inadequate sewage systems, a lack of public awareness about these diseases, and the unusual weather patterns in recent times.
Dr. Megnath Dhimal, an environmental health expert at the National Health Research Council, said that climate change is behind the unexpected rise in dengue cases since the first case was reported in 2004, diagnosed in a Japanese citizen coming from Japan.
He further stated that climate change is occurring worldwide, with the Himalayan region, including Nepal situated in the Hindu-Kush Himalayan Range, being the most impacted.
Dr. Dhimal shared that vector-borne diseases, including malaria, dengue, zika, yellow fever, chikungunya, and kala-azar, are commonly transmitted by the Aedes mosquito, posing significant public health challenges worldwide, especially in resource-constrained health settings like Nepali villages.
Shrestha also noted an increase in malaria cases in Kathmandu, a phenomenon that was previously unheard of in the region.
According to the Epidemiology and Disease Control Division under the Ministry of Health and Population, as of December 2023, there have been 51,243 reported dengue cases, 20 confirmed deaths, and 16 districts with more than 500 cases. The disease has spread across all 77 districts in the country.
Turning challenges into opportunities
Although climate change has led to the rise of vector-borne diseases, including dengue, the challenges posed by these ailments should be viewed as an opportunity to eradicate the diseases once and for all, Dr. Dhimal shared.
"Unlike in developed nations where cases are detected and eliminated before they escalate, in places like ours, due to resource constraints, these diseases don't receive attention until they reach pandemic proportions," Dr. Dhimal said.
Due to the rise in temperature, mosquitoes cannot survive beyond 35 degrees Celsius. Consequently, they move to higher altitudes where they find more favorable temperatures to adapt. As a result, the effects of climate change are more keenly felt in higher altitude regions, clarified Dr. Dhimal.
He further noted an increase in the presence of venomous snakes in the hilly regions, which were commonly found in the low plains of the Terai region in the past. "The government needs to establish snake bite treatment centres in the hilly regions before the situation escalates beyond control in these highlands."
Shrestha believes that the local government is not taking sufficient measures to control vector-borne diseases in the area. She urged the authorities to act swiftly to prevent outbreaks in the region and across the nation.
Way forward
According to Dr. Dhimal, diseases such as kala-azar, malaria and snakebites will increasingly outbreak in hilly areas due to the more favourable environment resulting from the unexpected rise in climate change.
"It's a challenge of the 21st century and an opportunity to address these issues," he stated. "This can be resolved by adopting a systematic health system in the nation. These issues have persisted from the past to the present, so to address them today, we must develop a climate-resilient health system," clarified Dr. Dhimal.
He outlined six pillars in the health system, including leadership and governance with a climate-transformative approach, the development of a separate wing to oversee health and climate change, the appointment of a focal person and adequate budget under the Ministry of Health and Population, climate-smart health professionals, research and development, and a health information system.
Dr. Dhimal emphasised the need to change procurement policies and healthcare building designs to accommodate climate-resilient facilities.
"Though we have a climate-sensitive disease surveillance system, it needs to be made more effective in the coming days," said Dr. Dhimal.
"We need to create a proactive early warning and response system. Unfortunately, we currently have an early warning and reporting system that needs updating," Dr Dhimal said adding although efforts have been made to cover many areas, we are still unsatisfied and more needs to be done.
Shrestha feels that something is amiss with the unprecedented disease outbreaks, unpredictable weather, sweltering heat, and air pollution. "I have lived my life," she said, "but what about the coming generations? Will they experience the same quality of life we once had?"
Meanwhile, local government authorities have advised citizens to take precautionary measures against dengue fever infection due to the rising temperatures and the approaching monsoon season.
