by Jake Kessler
Vector-Borne diseases continue to burden a large portion of the world with negative health and economic impacts. According to several health specialists (Campbell-Lendrum et al. 2015) from the World Health Organization, there has been a surge in scenario-based modeling when dealing with the way climate change affects vector-borne diseases. However, they argue that the best way to deal with these diseases would be a decreased reliance on scenario based models for disease predictions, and an increase in short-term tactics to deal with “current disease rates and manage short term climate risks, which will, in turn increase resilience to long-term climate change.”
Vector-borne diseases are highly dependent on climate for their spread, but it is difficult to anticipate how climate change will affect that spread. Direct connections between climate change and vector borne diseases include temperature, precipitation, and humidity. There is a number of indirect effects which produce “wider effects on the natural environment and on human systems.” As a result of the varied connections, “the complexity of these interactions means that the effect of climate change, and the nature and extent of interaction with non-climate factors, varies markedly by diseases and locations.”
The authors looked at studies dealing with malaria and dengue fever to highlight different outcomes from modeling. Both diseases are predicted to become bigger burdens due to climate change, but malaria can be defeated by increasing efforts to combat poverty, funding for health infrastructure, and dealing with drug resistance. Dengue fever, is much less controllable through these avenues, and non-climactic factors are “expected to amplify, rather than oppose, the effects of climate change.”
Attributing disease transmission changes to climate change at the local level is difficult because of the long time frames needed for the data. Scenario modeling faces three problems in using climate data for current decisions when dealing with disease. First, they are too long-term and too broad. Second, they are too focused on basic mechanisms, like temperature, instead of mechanisms that are more difficult to simulate or measure, such as precipitation. Third, disease projections are based on future decisions which may, or may not, happen. All these flaws in scenario analysis make it less helpful for making disease control decisions. The most concrete way to control vector-borne diseases is to broaden approaches to controlling diseases rather than to focus on climate change and its specific effects on disease. The authors sum up the way policies should work by claiming that the best way to deal with disease transmission is to focus on current disease rates rather than planning for the unpredictable future.
I understand their claim that more needs to be done to focus on present battles with vector-borne disease transmission. It is dubious to base decisions on scenarios that are often incorrect. However, there is something to be said about planning for the future. Tackling these diseases now is a good decision, but ignoring climate change and its likely effects seems hopelessly optimistic. I would, like the authors, like to see more investment in scenario-analysis technology which would help alleviate some of the problems the authors have outlined.
Campbell-Lendrum D, Manga L, Bagayoko M, Sommerfeld J. 2015 Climate change and vector-borne diseases: what are the implications for public health research and policy? Phil. Trans. R. Soc. B 370: 20130552. http://dx.doi.org/10.1098/rstb.2013.0552
Focus on the now, rather than the future to deal with vector-borne disease #climatechange #accuracy #newplan