Reports in July of chikungunya outbreaks in Central America and the Caribbean, reports of the Ebola virus epidemic in West Africa and more recently Congo reminds us of the potential significance of disease as a threat to civilisation. WHO’s Disease outbreak news service (DONS) is a useful location for current outbreak news and it also contains links to archived reports. At the time of writing, DONS has reported in the last couple of months on the following reporting MERS-CoV (Middle East respiratory syndrome coronavirus), Ebola virus disease [latest report 30/8/14 of a first case in Senegal] and avian influenza A(H7N9).
Research into understanding of the spread of disease has a number of key interpretations. Mayer (1996) for example provides a useful introduction to a political ecology approach to understanding the spread of disease, one that has resonance with some of today’s important diseases. This emphasises the complex interactions between the environment and the outbreaks of disease. Thus changing the environment can have an impact on vulnerability of populations to disease. This link between environment and disease is illustrated in Paterson et al’s (2004) study of Ebola and Marburg disease epidemiology. They find as a result of modelling based on data from actual outbreaks of Ebola and Marburg disease (both haemorrhagic fever diseases) that there are routes and reservoirs that can have their function in the epidemiology of the disease strengthened or weakened depending on certain geographical features of the environment, such as temperature, elevation or land cover. Alternatively, Glass (2000) shows how certain spatial patterns area apparent in the epidemiological study of disease depending on the particular medium of disease transmission. This work suggests that what we have discovered about the links between disease and geography may change as our environment changes due to short to medium term climate oscillations and long term climate change, such as has been reported in relation to mosquito-borne diseases such a global review by Reiter (2001), analysis of diarrheal diseases in the Pacific Region by Singh et al (2001) and a WHO (2010) case study report on effects of climate change on diarrheal diseases and malaria in a region of Nepal. inerestingly the WHO report shows that the data on the physical processes of climate change is of good quality, but the data quality on disease is poor. This latter report concludes that there is more research work to be done to better understand these threats to civilisation.
HealthMap.org – a very interesting site – provides an interactive map of the spread of the ebola disease.
Glass, G. (2000) Update: Spatial aspects of epidemiology: the interface with medical geography. Epidemiological Reviews. 22(1), 136-139 [also available here]
Mayer, J (1996) The political ecology of disease as one focus for medical geography. Progress in Human Geography 20(4), 441-456. [also available here]
Reiter, P. (2001) Climate change and mosquito-borne diseases. Environmental Health Perspectives 109 (Supplement 1), 141-161. [Also available here]
Singh, R. B. K., Hales, S., de Wet, N., Raj, R. Hearnden, M. & Weinstein, P. (2001) The influence of climate variation and change on diarrheal disease in the Pasific Islands. Environmental Health Perspectives 109(2), 155-159. [also available here]
Townsend Peterson, A., Bauer, J. T. & Mills, J. N. (2004) Ecologic and geographic distribution of filovirus disease. Emerging Inectious Diseases. 10(1), 40-47. [also available here]
WHO (2010) Evaluation of the Effects of Climatic Factors on the Occurrence ofDiarrheal Diseases and Malaria:A Pilot Retrospective Study in Jhapa District, Nepal. World Health Organisation Technical Report, Kobe City. [available here]