SEATTLE — Climate change is altering ecosystems in ways that have far-reaching, adverse consequences for health. Mountain environments are particularly vulnerable, as the rate of warming increases with elevation.
Bhutan, a small, landlocked country in the Himalayas surrounded by China and India, has the highest average elevation (3,280m) in the world. Climate change-related temperature variations and rising mean temperatures have already been observed in the region.
The projected effects of climate change in Bhutan include increasingly frequent floods and landslides, receding glaciers and changes in vector species’ geographical distribution and abundance. All of these projected effects are associated with an increased risk of infection for climate-sensitive diseases in Bhutan.
Vector species are climate sensitive, requiring warmer conditions to breed and transmit infections; higher mean temperatures will likely increase the population of vector species and lengthen the transmission seasons of vector-borne diseases in Bhutan.
Climate change and warming will challenge water availability and safety in Bhutan. Floods, landslides, glacial recession and rain pattern changes will alter the water in ways that enhance contamination and the risk of waterborne diseases. Below is a list of the climate-sensitive diseases in Bhutan:
- Malaria
Malaria is a mosquito-borne disease transmitted through the bite of an infected female Anopheles mosquito. Plasmodium falciparum and Plasmodium vivax are two types of malaria that are common in Bhutan. Plasmodium falciparum is more severe and accounts for 30 to 60 percent of malaria cases. - Dengue
Dengue is a relatively new infectious disease in Bhutan; though it was not detected until 2004, dengue is now endemic in Bhutan during the monsoon period, with seven to 10 cases detected daily. Dengue is a mosquito-borne viral infection transmitted through the bites of an infected female Aedes aegypti or Ae. albopictus mosquitos. Between 2004 and 2012, 3,083 cases were detected in Bhutan’s Phuentsholing Hospital. - Diarrheal Diseases
Diarrheal disease incidence has also increased in Bhutan, accounting for 10 to 15 percent of Bhutan’s annual morbidity. Nearly 20,000 Bhutanese children under age five are treated for diarrheal diseases each year.
Bhutan’s government has endorsed advancement and adaptation measures for climate change mitigation as a strategy for improving public health and reducing incidences of waterborne and vector-borne diseases. One effort is the Water Safety Plan (WSP), which is being implemented in Bhutan to improve drinking water safety and supply.
In addition to the WSP, Bhutan is included in the Piloting Climate Change Adaption to Protect Public Health initiative developed by the World Health Organization and the UNDP-Global Environment Facility. Part of the Bhutanese initiative involves organizing climate data with epidemiological assessments for climate-sensitive diseases in Bhutan. With advancements in drinking water quality and climate-change epidemiology, reductions in climate-sensitive diseases in Bhutan are expected.
– Gabrielle Doran
Photo: Flickr