The health authorities thought they had almost gotten rid of it, but it slowly resurfaced.
Nepal is worried about a resurgence of dengue fever on its territory, a consequence of climate change and urbanization.
The statistics speak for themselves. In 2004, the Himalayan country recorded only four cases of this virus which causes high fevers which are sometimes fatal.
Since the start of this year, more than 28,000 people have already been infected, 12 have died. And doctors believe that these figures are probably underestimated.
It is a fact, the mosquitoes carrying dengue fever have started to invade the high Nepalese valleys.
Around twenty cases have been reported in the Solukhumbu district, that of the highest peak in the world, Mount Everest.
“There shouldn’t be any at all,” remarks local health official Suman Tiwari. “The most surprising thing is that even people who have never traveled have tested positive.”
More than 4,000 cases of dengue have also been reported in the capital Kathmandu alone, although located at an altitude of 1,400 meters.
“Unfortunately, (the virus) moves geographically,” confirms Dr Sher Bahadur Pun of Sukraraj Hospital. “It was previously only observed in certain regions, it climbs in the mountains and the foothills of the Himalayas.”
In some districts, hospitals are now overflowing with dengue patients.
“The number of cases is increasing exponentially,” says Dr. Pun. “With each epidemic, the number of infected people increases and I see more fatal cases.”
A global trend, according to the World Health Organization (WHO), which recorded more than 7,900 deaths and 12.3 million proven or reported cases in the first eight months of this year. Double that of the entire previous year.
For epidemiologists, the spread of the disease appears to be caused by changing temperatures and precipitation patterns, which allow Aedes aegypti mosquitoes to survive and breed at higher altitudes.
– “Annual” epidemics –
Nepalese virologist Narayan Gyawali also highlights the impact of urbanization and increased mobility of the population.
“Microclimates are created during the urbanization of an area, the temperature and humidity increase,” he notes, “it is an environment favorable to survival and reproduction.”
In Nepal, the epidemic has been growing steadily for three years. It peaked in 2022, with nearly 55,000 cases, including 88 deaths.
“Dengue was more of a cyclical disease. It now comes back every year. We must prepare to fight it annually,” insists Gokarna Dahal, of the Nepalese Ministry of Health.
An “unfair” situation, he adds, noting that his country’s responsibility for global warming is minimal but that Nepal is among those most impacted.
If the responsibility for ensuring the health protection of the population lies with the Nepalese state, agrees Meenakshi Ganguly of the NGO Human Rights Watch (HRW), those mainly responsible for climate change must do their part.
“The countries that emit the most greenhouse gases must do much more to protect the populations of countries like Nepal from the consequences of warming,” she judges.
“Fighting mosquito-borne diseases like dengue, which are spreading rapidly to new areas, must be part of this effort,” insists Meenakshi Ganguly.
Dengue is already endemic in more than 130 countries around the world, according to the WHO.
The UN organization has launched a global plan to coordinate the fight against the virus, for which it has requested a budget of 55 million dollars (50 million euros) for 2025.
Some four billion people worldwide — half the world’s population — are at risk of contracting dengue and other arboviruses, including chikungunya and zika, the WHO has warned. This number is expected to reach five billion by 2050.
pm/pa/tmt
