Role of Integrated Vector Management for Prevention and Control of Japanese Encephalitis/ Acute Encephalitis Syndrome (JE/ AES) - A Review

In recent years, vector borne diseases (VBDs), have emerged as a serious public health problem. Repeated outbreaks of viral diseases, particularly Dengue fever, Chikungunya and Japanese Encephalitis (JE) are reported in the country. JE/AES is a main public health problem and is causing high mortality and disability. JE is a mosquito borne zoonotic viral disease and virus is maintained in animals, birds (Cattle egrets, pond herons etc.) and in pigs (amplifier hosts). JE is now an emerging viral disease having international importance because it is invading the previously non-endemic areas and major public health problem due to high case fatality rate and disability. JE/AES is currently reported from 25 states and Union Territories of India and repeated outbreaks are reported from eastern Uttar Pradesh, Bihar and Assam. The risk factors, which play a key role in the spread and transmission of JE are, ecological changes due to developmental activities and climate change, expansion of agriculture, change of irrigation and crop pattern, constructions of irrigation and dams, poor environmental sanitation, migratory birds’ movement etc.. Vector ecology mostly determines the disease distribution. Factors that make the prevention and control of JE challenging are-outdoor habit of the vector, scattered distribution of cases spread over relatively large areas, role of different reservoir hosts making it difficult to control JE. Transovarial transmission is also known in the maintenance of JE virus. These are causes for much concern and highlight the need to comprehensively address the challenges faced in combating this disease in the country. There is a constraint to control JE due to its complex eco epidemiological ecology and entomological factors. Integrated vector management (IVM) is one of the key elements of vector control strategy and to reduce or interrupt transmission of disease. An IVM approach takes into account the available health infrastructure, resources and integrates all available and effective measures, whether chemical, biological, or environmental. This article provides an overview of IVM, along with all options available for prevention and control of JE.