Knowledge Synthesis Protocols
Permanent URI for this collection
Browse
Recent Submissions
Item Embargo Revisiting the role of swine on the risk of Japanese Encephalitis Virus (JEV) transmission in the United States: a rapid systematic review of the literature(Kansas State University, Center for Outcomes Research and Epidemiology, 2023-04) Veloso, Vanessa De Aguiar; Hanthorn, Christy J.; Dixon, Andrea L.; Cernicchiaro, NataliaJapanese Encephalitis (JE) is an emerging, zoonotic disease caused by the Japanese encephalitis virus (JEV), which is transmitted primarily by Culex species mosquitoes (particularly Culex tritaeniorhynchus). The JEV maintains its life cycle between mosquitoes and vertebrate hosts, primarily pigs and wading birds (Le Flohic et al., 2013). In humans, JEV infection causes inflammation of the brain (encephalitis) as well as fever, headache, respiratory distress, gastrointestinal pain, confusion, seizures, and, in some cases, death (Fischer et al., 2012; Hills et al., 2014). The global incidence of JE is uncertain. Effectiveness and quality of JE surveillance in endemic countries vary (Jayatilleke et al. 2020), as does availability of diagnostic testing throughout the world. Between 50,000 and 100,000 JE cases per year are estimated to occur in endemic countries (WHO, 2006; Campbell et al., 2011, Quan et al., 2020). Among all clinical cases, children under the age of 10 comprise the majority affected (WHO, 2006). Whereas less than 1% of the cases are accompanied by symptoms, 30% of the symptomatic cases are fatal (Campbell et al., 2011). Being untreatable and incurable, once introduced in a community, JE can lead to devastating economic and health impacts. The United States (US) is considered a susceptible region with great potential for JEV introduction. The availability of competent vectors, susceptible maintenance hosts (avian), intensive travel and trade activities to and from JEV-affected countries, areas with similar climatic and environmental conditions to countries where the virus is epidemic, and large populations of susceptible, amplifying hosts (domestic and feral pigs), makes the US suitable for JEV emergence. In fact, the US is the world’s third-largest producer and consumer of pork and pork products (ERS, USDA 2022). The importance of the swine industry to the US economy and the sizeable naïve pig populations, magnify the severity of a potential viral incursion. As pigs are considered the main amplifying host of JEV, an extensive review of the literature and identification of knowledge gaps will assist researchers, stakeholders, and policy makers with effort prioritization, development of precautionary intervention measures, and evaluation of disease control measures. Although current conditions have not been favorable for JEV to establish in the US, increases in international trade and globalization, as well as changes in climate and land use, and reductions in pesticide use, can contribute to its rapid and wide geographical spread (Oliveira et al., 2018). A good understanding of the role of swine as an amplifying host for this virus is critical to public health authorities when planning prevention and preparedness measures.Item Open Access Assessment of data on vector and host competence for Japanese encephalitis virus: A systematic review update of Oliveira et al. 2018(2022-08-19) Dixon, Andrea L; Edache, Stephen; Oliveira, Ana R. S.; Veloso, Vanessa De Aguiar; Cernicchiaro, NataliaJapanese Encephalitis (JE) is an emerging, zoonotic disease transmitted primarily by Culex species mosquitoes (particularly Culex tritaeniorhynchus) carrying the flavivirus Japanese encephalitis virus (JEV). Japanese encephalitis virus maintains its life cycle between mosquitoes and vertebrate hosts, primarily pigs and wading birds (Le Flohic et al., 2013). JE is an untreatable and incurable disease that, in humans, can result in inflammation of the brain (encephalitis) causing fever, headache, respiratory signs, gastrointestinal signs, confusion, seizures, coma, and, in some cases, death (Fischer et al., 2012; Kliegman et al., 2015). The United States (US) is considered a susceptible region with great potential for JEV introduction, given the availability of competent insect vectors, susceptible maintenance (avian) hosts, large populations of susceptible, amplifying hosts (domestic and feral pigs), intensive travel and trade activities to and from JEV-affected countries, and areas with similar climatic and environmental conditions to countries where the virus is epidemic. To investigate the risk of JEV introduction and establishment, Oliveira and colleagues performed a risk assessment (Oliveira et al., 2019) supported by a systematic review of vector and host competency for JEV (Oliveira et al., 2018). 3Although Oliveira et al. (2019) found the risk of introduction of JEV in the US through entry of infected mosquitoes via airplanes to be very high, the risk of establishment was considered negligible; yet, increases in international trade and globalization, as well as changes in climate and land use, and the recent incursion of a new JEV genotype into areas previously free from disease, as observed in Australia with the invasion and expansion of JEV (Genotype IV) in the eastern and southeastern states, warrants the need for an update of the review and risk assessment. The objective of this review is to update the systematic review (Oliveira et al., 2018) on host and vector competence of transmission of the Japanese encephalitis virus.
