Japanese encephalitis virus review: Placing disease vectors in the epidemiologic triad

Authors: OLIVEIRA, ANA - Kansas State University; Cohnstaedt, Lee; CERNICCIARO, NATALIA - Kansas State University

Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/20/2018
Publication Date: 8/2/2018
Citation: Oliveira, A., Cohnstaedt, L.W., Cernicciaro, N. 2018. Japanese encephalitis virus review: Placing disease vectors in the epidemiologic triad. Annals of the Entomological Society of America. https://doi.org/10.1093/aesa/say025.
DOI: https://doi.org/10.1093/aesa/say025

Interpretive Summary: The Japanese encephalitis virus (JEV) is a mosquito transmitted disease in South and Southeast Asia, and the Western Pacific Rim. The virus can result in Japanese encephalitis which is considered the main viral encephalitis in the region, affecting mainly children up to 14 years old. The virus has a complex transmission cycle consisting of mosquitoes and reservoir hosts such as pigs and ardeid (wading) birds as reservoir hosts. Environmental, ecological, and social determinants play an important role on the epidemiology of JE and JEV, as well the spread of the virus to new territories. Japanese encephalitis has no cure; thus, efforts are put forth towards prevention and control by reducing exposure to potentially infected mosquitoes or vaccination. The epidemiological triad classically consists of agent, host, and environment. However with vector-borne diseases (arthropod transmitted pathogens), the vector plays a vital role and without the vector there is no pathogen transmission. By not emphasizing the importance of the arthropod vector, the role of the vector is often neglected or under appreciated. The sections below cover the most important aspects of JE and JEV, providing a summary of the current knowledge, and place it in context of a new epi triad.

Technical Abstract: The Japanese encephalitis virus (JEV) is the causative agent of Japanese encephalitis (JE), a vector-borne zoonosis that affects most countries in South and Southeast Asia, and the Western Pacific Rim. It is considered the main cause of viral encephalitis in that region, affecting mainly children up to 14 years old. The virus is transmitted by mosquitoes, particularly of the Culex genus, and the transmission cycle is complex, involving pigs and ardeid birds as reservoir hosts. Environmental, ecological, and social determinants play a paramount role on the epidemiology of JE and JEV, as well as on its geographical expansion over new territories. Japanese encephalitis has no cure; thus, efforts are put forth towards prevention and control by reducing exposure to potentially infected mosquitoes or vaccination. The epidemiological triad classically consists of agent, host, and environment. However with vector-borne diseases (arthropod transmitted pathogens), the vector plays a vital role and without the vector there is no pathogen transmission. By not emphasizing the importance of the arthropod vector, the role of the vector is often neglected or under appreciated. The sections below cover the most important aspects of JE and JEV, providing a summary of the current knowledge and place it in context of a new epi triad.