The impact of climate change on the transmission and incidence of directly-transmitted childhood infectious diseases

Authors: Rachel Baker1, Ayesha Mahmud1
Author Affiliations: 1Princeton University

Climate change may alter the spread of directly transmitted infections as climatological factors such as relative humidity and temperature affect the suspension of disease-carrying droplets. This impact remains relatively understudied for many directly-transmitted infections. Using a unique long-term dataset from Mexico, in conjunction with statistical and analytical tools from both infectious disease biology and climatology, we test for associations between climatic conditions and incidence of three common childhood infections. We find that drier conditions (lower humidity) increases the transmission of the varicella virus after controlling for seasonality and long term changes in incidence, which is consistent with previous findings for influenza. Temperature is not found to have a significant effect on transmission. In ongoing work we are testing these associations for scarlet fever and RSV.

The second contribution of this paper is to synthesize alternate methods for estimating climate-transmission relationships. We estimate the unobserved transmission rates from the incidence data using a mechanistic disease transmission model. We combine these estimates with panel regression methods to estimate the effect of environmental variables on transmission, allowing construction of projection models. Finally, we formally evaluate our ability to detect an effect of climate change from incidence data using simulations to reflect increasing degrees of stochasticity and underreporting across a broad range of driving relationships between climate and transmission.

Climate Change Epidemiological Health Reports in Michoacan State, Mexico since 2009 to 2015

Authors: Alejandro Molina-Garcia1, C. Armendariz-Arnez2, L. Pacheco-Magaña3, G. Figueroa-Aguilar4, LA. Saavedra-Romero5, CE. Aranza-Doniz6, J. Martinez-Ponce7
Author Affiliations: 1Climate Change and Health State Leadership, medical doctor; 2State Commission for Protection Against Sanitarian Risks, Ministry of Health at Michoacan State, Morelia, Mexico; 3National University Autonomous of Mexico, ENES Campus Morelia, Morelia, Mexico; 4State Laboratory of Public Health, Ministry of Health at Michoacan State, Morelia, Mexico; 5Technical Secretary, Ministry of Health at Michoacan State, Morelia, Mexico; 6Minister of Health, Ministry of Health at Michoacan State, Morelia, Mexico; 7Ministry of Health, Ministry of Health at Michoacan State, Morelia, Mexico.

Objective: To show the epidemiological reports of the impact on health with local and global environmental change. Data sources: our main reports were measured with parameters like temperature and precipitations during 1950-2000; and climate change scenarios projected to 2020-2030-2050. Also, ozone like air pollutant, 2009 pandemic A/H1N1 spring outbreak; floodings and acute respiratory and diaorrheal infectious diseases, dermatitis and conjunctival diseases related with contaminated food, air, water and soil after intense rainfalls; surveillance of vibrio parahaemolyticus; ocean pH and enterococcus. Methods: Samples were obtained and sent to state public health laboratory in Morelia, Michoacan, Mexico. Meteorological reports were obtained and reviewed by the Delegational state of the National Commision of Water and analysed by the Athmosferic Science Center from the National University Autonomus of Mexico in Mexico City. Descriptive epidemiological reports were assessed to complete these reports from the epidemiological surveillance health system of Michoacan. Results: Acute infectious diseases were identified like A/H1N1 flu virus and ozone air pollutant in april and may in 2009. Respiratory and diaorrheal infectious outbreaks in heavy rainfalls and floodings in 2010 february in the Monarch butterfly biosphere region in East Michoacan. In the same year, in april an outbreak of vibrio parahaemolyticus were presented. And, recently in 2013 a serial reports related with a low level pH decrease in the Pacific ocean coast and the presence of enterococcus were measured. All these results were associated with temperature, precipitations and climate change scenarios since 1950-2000 and 2020, 2030 and 2050 measures in Michoacan. Conclusions: Climate change and its impact on human health is a global health concern. Acute and infectious diseases were identified in places where our temperature and precipitations are increasing like world reports in ar4 and ar5 IPCC and others epidemiological data have been publishing.

Fighting climate change with the power of water

Authors: Ashley Aimone1, Paula Braitstein1, Donald Cole1, Andrea Cortinois1
Author Affiliations: 1Dalla Lana School of Public Health, University of Toronto

As the era of the Anthropocene unfolds, and climate/environmental change (CEC) becomes more of a concern, there is also a large and persistent gap between what is known about the future of the planet’s health and what the global health community is presently doing about it. Water insecurity is a central driver of many food security and health inequities related to CEC. Not only does CEC affect the availability of fresh and clean water (e.g. through droughts or floods leading to chemical waste runoff from industrial agriculture), it also exacerbates existing political tensions and power struggles around water security (e.g. due to irrigation schemes moving water away from poorer to richer farmers, or the activities of transnational corporations, or the fracking industry). In fact, unlike food systems which are extremely complex and impacted by several heterogeneous factors, water can be more clearly linked to power as the central issue affecting availability and access. Therefore, we hypothesize that water sovereignty can provide a means of achieving water sustainability and security, through the strengthening of local rights and control over the supply and use of water, while protecting biodiversity, and local economies. To explore this hypothesis, we are conducting a review to determine the state of knowledge with respect to water sovereignty and its demonstrated or perceived potential for promoting water security and sustainability; and thus improved health equity across local and global scales and for future generations. Despite the perceived benefits of water sovereignty, there is a lack of knowledge or guidance in terms of how to achieve this within political systems that are dominated by globalized corporatist or macro-development interests.

%d bloggers like this: