Geoecology of malaria in India: Historical perspective and a case study of western Rajasthan

Abstract

Malaria has plagued India since antiquity. In the twentieth century, both man-made and physical environments have contributed to the establishment of different malaria intensity zones. All the development and progress in science has not been able to conquer this disease, although it has been held at bay for at least half a century in many regions of the world. However, India is not among these regions; its conducive climate, lack of resources and fluxes in political will and stability have rendered it highly malaria prone. Considering that this risk of malaria persists to this day despite multiple and sustained efforts, an attempt has been made to highlight India’s past experience in order to mount an informed and organized offensive to combat malaria. A 1948 Malaria Distribution Map of India indicated malaria–free, endemic and variable endemic zones. The malaria-free zone was associated with higher elevations, e. g. the Himalayas and coastal lands. The endemic zone was considered to be places where the average annual rainfall exceeded 80 cm. A malaria control program was started in India immediately after independence in 1947. Spraying of Anopheles-killing insecticides was the main control activity. Although the disease was largely controlled by 1965, resurgence took place from several pockets. Monsoon rains, higher humidity, vegetation, tribal habitats and rice cultivation have definitive associations with the disease in those two states. Eradication will have to await the discovery of an effective vaccine, but the disease has been drastically controlled since the mid-1980s with the existing techniques. However, the Intergovernmental Panel on Climate Change (IPCC) Assessment Report of 2007 asserts that climate change contributes to the global burden of disease and premature deaths. Population is exposed to climate change through changing weather pattern—temperature, precipitation and more frequent extreme events such as heat waves, cyclones and flooding. In the context of health, there is emerging evidence that climate change has altered the distribution of some infectious disease vectors and has increased heat wave-related deaths. This chapter discusses the outbreak of malaria in the desert region of Rajasthan and also focuses on the study of people–s perception about climate change and its impact.