New project to study effect of climate change on society's vulnerability to dengue fever

New research project will study how changes and variations in climate affect a society's vulnerability and risk of mosquito-transmitted diseases, particularly dengue fever, in Southeast Asia.

Dengue fever is the most rapidly spreading mosquito-transmitted viral disease in the world. It causes roughly 390 million infections and 22,000 deaths annually. There is currently no cure and a recently licensed vaccine does not give complete protection.

The research project «Effects of climate change and variability on community vulnerability and exposure to dengue in South East Asia» was recently awarded NOK 10 million by the KLIMAFORSK program of The Research Council of Norway. It is also co-funded by Norwegian University of Life Sciences (NMBU). The project will officially start at a partner meeting in Khon Kaen in northeastern Thailand on 29-30 January 2018.

The project will take a multidisciplinary approach to mapping changes and variations in climate and how these affect a society's vulnerability and risk of dengue fever along the Mekong river in Laos and Thailand.

Hans Overgaard of NMBU's Faculty of Science and Technology is the principal investigator of the project. He has long-term experience from the region and with vector-borne diseases such as malaria and dengue. He is also leading another project on dengue in northeastern Thailand.

"Climate change is currently one of the most important emerging global concerns. It affects health directly by exposure to climatic extremes and indirectly through impacts on water quality and quantity, temperature, social infrastructure or through direct effects on secondary organisms, such as disease vectors. Southeast Asia is considered one of the most vulnerable regions affected by climate change," says Overgaard.

In the project, disease surveillance, mosquito infestation, meteorology, socioeconomics, knowledge, attitudes and practices, and land cover will be combined with future climatic scenarios and population growth trends to predict potential changes in dengue risk factors and community vulnerabilities in border areas of these two countries.

"The project is complicated logistically, but I am very happy to be able to collaborate with a great team of international partners," says Overgaard.

These are Khon Kaen University and Asian Institute of Technology, both in Thailand; University of Health Sciences in Laos; Pasteur Institute in Paris; Umeå University in Sweden; and Baldwin Wallace University in the USA.

"Assessing these factors is instrumental in developing adaptation strategies at local and regional levels, because assessing potential health impacts of climate change and climate variability requires understanding of the vulnerability of a population and its capacity to respond to new conditions. The study countries are vulnerable to both direct and indirect effects of climate change," says Overgaard.

Dengue, Zika and chikungunya are arboviruses transmitted by mosquito vectors. Higher temperatures affect mosquito and virus development, and rainfall may increase mosquito proliferation. So far, no comprehensive models measures climate-induced vulnerability, vector ecology, and socio-economic conditions, with disease dynamics and their impact on dengue incidence.

Dengue is often mapped on a global scale, but its distribution is often driven by local patterns influenced by fine-scale, socio-economic, environmental, virological, and demographic factors.

"Climate change is expected to have numerous negative environmental impacts in Laos and Thailand, such as increased temperatures, more warm days, higher rainfall variability, flooding and droughts, which may result in detrimental effects on public health, including dengue. Both countries have different adaptive capacities due to differences in landscape and land cover, as well as political, and socioeconomic development," says Overgaard, adding that project results obtained for dengue, may also be applicable to Zika and chikungunya.

"I hope in the end of the project, we can provide results that will be helpful for governments to control dengue and opportunities for people to live healthy lives," concludes Overgaard.

The Research Council of Norway received 89 proposals to the call for research projects on the impacts of climate change. The total amount applied for was NOK 797 million. The call sought grant proposals for research projects on the impacts of climate change on society of particular relevance to the public administration and important land-based industrial sectors and research projects on the impacts of climate change on terrestrial ecosystems, including fresh water and the physical natural environment.