-
Virulence Dec 2021Thousands of human deaths occur annually due to Japanese encephalitis (JE), caused by Japanese encephalitis virus. During the virus infection of the central nervous... (Review)
Review
Thousands of human deaths occur annually due to Japanese encephalitis (JE), caused by Japanese encephalitis virus. During the virus infection of the central nervous system, reactive gliosis, uncontrolled inflammatory response, and neuronal cell death are considered as the characteristic features of JE. To date, no specific treatment has been approved to overcome JE, indicating a need for the development of novel therapies. In this article, we focused on basic biological mechanisms in glial (microglia and astrocytes) and neuronal cells that contribute to the onset of neuroinflammation and neuronal cell damage during Japanese encephalitis virus infection. We also provided comprehensive knowledge about anti-JE therapies tested in clinical or pre-clinical settings, and discussed recent therapeutic strategies that could be employed for JE treatment. The improved understanding of JE pathogenesis might lay a foundation for the development of novel therapies to halt JE. AKT: a serine/threonine-specific protein kinase; AP1: activator protein 1; ASC: apoptosis-associated speck-like protein containing a CARD; ASK1: apoptosis signal-regulated kinase 1; ATF3/4/6: activating transcription factor 3/4/6; ATG5/7: autophagy-related 5/7; BBB: blood-brain barrier; Bcl-3/6: B-cell lymphoma 3/6 protein; CCL: C-C motif chemokine ligand; CCR2: C-C motif chemokine receptor 2; CHOP: C/EBP homologous protein; circRNA: circular RNA; CNS: central nervous system; CXCL: C-X-C motif chemokine ligand; dsRNA: double-stranded RNA; EDEM1: endoplasmic reticulum degradation enhancer mannosidase alpha-like 1; eIF2-ɑ: eukaryotic initiation factor 2 alpha; ER: endoplasmic reticulum; ERK: extracellular signal-regulated kinase; GRP78: 78-kDa glucose-regulated protein; ICAM: intercellular adhesion molecule; IFN: interferon; IL: interleukin; iNOS: inducible nitric oxide synthase; IRAK1/2: interleukin-1 receptor-associated kinase 1/2; IRE-1: inositol-requiring enzyme 1; IRF: interferon regulatory factor; ISG15: interferon-stimulated gene 15; JE: Japanese encephalitis; JEV: Japanese encephalitis virus; JNK: c-Jun N-terminal kinase; LAMP2: lysosome-associated membrane protein type 2; LC3-I/II: microtubule-associated protein 1 light chain 3-I/II; lncRNA: long non-coding RNA; MAPK: mitogen-activated protein kinase; miR/miRNA: microRNA; MK2: mitogen-activated protein kinase-activated protein kinase 2; MKK4: mitogen-activated protein kinase kinase 4; MLKL: mixed-linage kinase domain-like protein; MMP: matrix metalloproteinase; MyD88: myeloid differentiation factor 88; Nedd4: neural precursor cell-expressed developmentally downregulated 4; NF-κB: nuclear factor kappa B; NKRF: nuclear factor kappa B repressing factor; NLRP3: NLR family pyrin domain containing 3; NMDAR: N-methyl-D-aspartate receptor; NO: nitric oxide; NS2B/3/4: JEV non-structural protein 2B/3/4; P: phosphorylation. p38: mitogen-activated protein kinase p38; PKA: protein kinase A; PAK4: p21-activated kinase 4; PDFGR: platelet-derived growth factor receptor; PERK: protein kinase R-like endoplasmic reticulum kinase; PI3K: phosphoinositide 3-kinase; PTEN: phosphatase and tensin homolog; Rab7: Ras-related GTPase 7; Raf: proto-oncogene tyrosine-protein kinase Raf; Ras: a GTPase; RIDD: regulated IRE-1-dependent decay; RIG-I: retinoic acid-inducible gene I; RIPK1/3: receptor-interacting protein kinase 1/3; RNF11/125: RING finger protein 11/125; ROS: reactive oxygen species; SHIP1: SH2-containing inositol 5' phosphatase 1; SOCS5: suppressor of cytokine signaling 5; Src: proto-oncogene tyrosine-protein kinase Src; ssRNA = single-stranded RNA; STAT: signal transducer and activator of transcription; TLR: toll-like receptor; TNFAIP3: tumor necrosis factor alpha-induced protein 3; TNFAR: tumor necrosis factor alpha receptor; TNF-α: tumor necrosis factor-alpha; TRAF6: tumor necrosis factor receptor-associated factor 6; TRIF: TIR-domain-containing adapter-inducing interferon-β; TRIM25: tripartite motif-containing 25; VCAM: vascular cell adhesion molecule; ZO-1: zonula occludens-1.
Topics: Animals; Apoptosis; Cell Death; Encephalitis Virus, Japanese; Encephalitis, Japanese; Endoplasmic Reticulum Chaperone BiP; Humans; Inflammation; Mice; Nervous System Diseases; Neurons; Proto-Oncogene Mas; Signal Transduction; Virulence
PubMed: 33724154
DOI: 10.1080/21505594.2021.1899674 -
The American Journal of Tropical... May 2023Japanese encephalitis (JE) is becoming an increasingly important issue among adults. The reasons for this are multifactorial. During the past decades, new areas of... (Review)
Review
Japanese encephalitis (JE) is becoming an increasingly important issue among adults. The reasons for this are multifactorial. During the past decades, new areas of Japanese encephalitis virus (JEV) transmission have occurred in several locations, most notably in a markedly expanded area of Australia during 2021-2022. When JEV enters new areas, cases in adults frequently occur. This is unlike the typical pattern in endemic areas where the burden of disease is in children because most adults are protected through natural immunity following earlier exposure to the virus. Even in endemic areas, JEV has become relatively more important in adults because improved JE control through childhood immunization programs has resulted in a substantial decrease in pediatric JE cases and thus more prominence of adult JE cases. Finally, increases in tourism to JE risk areas have resulted in more exposure of adult travelers, who are usually non-immune, to infection in JE risk areas. In this review we describe the increasing importance of JE in adults in some areas and then consider the comparative clinical presentation and severity of illness among children and adults.
Topics: Adult; Child; Humans; Encephalitis, Japanese; Encephalitis Virus, Japanese; Australia; Immunity, Innate; Immunization Programs; Japanese Encephalitis Vaccines
PubMed: 37037440
DOI: 10.4269/ajtmh.23-0036 -
Rhode Island Medical Journal (2013) Aug 2020Travelers to 24 endemic countries in Asia may be at risk for Japanese encephalitis. The ACIP has recently expanded guidelines on the use of Ixiaro, the inactivated... (Review)
Review
Travelers to 24 endemic countries in Asia may be at risk for Japanese encephalitis. The ACIP has recently expanded guidelines on the use of Ixiaro, the inactivated Japanese encephalitis vaccine. This article reviews the disease burden of Japanese encephalitis and the role of a travel clinic in guiding travelers to Asia regarding decision-making about the use of this highly protective vaccine.
Topics: Adolescent; Adult; Asia; Child; Child, Preschool; Encephalitis Virus, Japanese; Encephalitis, Japanese; Humans; Infant; Japanese Encephalitis Vaccines; Risk; Seasons; Travel
PubMed: 32752568
DOI: No ID Found -
Revue Scientifique Et Technique... Aug 2015Japanese encephalitis (JE) is an inflammation of the central nervous system in humans and animals, specifically horses and cattle. The disease, which can sometimes be...
Japanese encephalitis (JE) is an inflammation of the central nervous system in humans and animals, specifically horses and cattle. The disease, which can sometimes be fatal, is caused by the flavivirus Japanese encephalitis virus (JEV), of which there are five genotypes (genotypes 1, 2, 3, 4 and 5). The transmission cycle of the virus involves pigs and wild birds as virus amplifiers and mosquitoes as vectors for transferring the virus between amplifying hosts and to dead- end hosts, i.e. humans, horses and cattle. In horses and cattle the disease is usually asymptomatic, but when clinical signs do occur they include fever, decreased appetite, frothing at the mouth, rigidity of the legs and recumbency, and neurological signs, such as convulsive fits, circling, marked depression and disordered consciousness. In pigs, it can cause abortion and stillbirths. At present, the virus is detected in a wide area covering eastern and southern Asia, Indonesia, northern Australia, Papua New Guinea and Pakistan. JEV RNA has also been detected in Italy, first in dead birds in 1997 and 2000 and then in mosquitoes in 2010. Genotype shift, i.e. a change of genotype from genotype 3 to genotype 1, has occurred in some countries, namely Japan, South Korea, Chinese Taipei and Vietnam. Laboratory methods are available for confirming the causative agent of the disease. There are control measures to prevent or minimise infection and, among them, vaccination is one of the most important and one which should be adopted in endemic and epidemic areas.
Topics: Animals; Culex; Encephalitis Virus, Japanese; Encephalitis, Japanese; Genome, Viral; Humans; Insect Vectors; Zoonoses
PubMed: 26601447
DOI: 10.20506/rst.34.2.2370 -
CMAJ : Canadian Medical Association... May 2018
Topics: Encephalitis Virus, Japanese; Encephalitis, Japanese; Fatal Outcome; Fever; Headache; Humans; Immunoglobulins, Intravenous; Magnetic Resonance Imaging; Male; Middle Aged; Real-Time Polymerase Chain Reaction
PubMed: 29807939
DOI: 10.1503/cmaj.171341 -
Journal of Special Operations Medicine... 2016
Review
Topics: Asia; Encephalitis, Japanese; Endemic Diseases; Humans; Japanese Encephalitis Vaccines; Military Personnel
PubMed: 27450609
DOI: No ID Found -
Current Opinion in Neurology Jun 2023Vaccinations have been pivotal in lowering the global disease burden of vaccine-preventable encephalitides, including Japanese encephalitis, tick-borne encephalitis,... (Review)
Review
PURPOSE OF REVIEW
Vaccinations have been pivotal in lowering the global disease burden of vaccine-preventable encephalitides, including Japanese encephalitis, tick-borne encephalitis, measles encephalitis, and rabies encephalitis, among others.
RECENT FINDINGS
Populations vulnerable to vaccine-preventable infections that may lead to encephalitis include those living in endemic and rural areas, military members, migrants, refugees, international travelers, younger and older persons, pregnant women, the immunocompromised, outdoor, healthcare and laboratory workers, and the homeless. There is scope for improving the availability and distribution of vaccinations, vaccine equity, surveillance of vaccine-preventable encephalitides, and public education and information.
SUMMARY
Addressing these gaps in vaccination strategies will allow for improved vaccination coverage and lead to better health outcomes for those most at risk for vaccine-preventable encephalitis.
Topics: Humans; Female; Pregnancy; Aged; Aged, 80 and over; Vulnerable Populations; Encephalitis, Japanese; Vaccination; Encephalitis
PubMed: 37078664
DOI: 10.1097/WCO.0000000000001158 -
Acta Tropica Sep 2018Japanese encephalitis (JE) is a vector-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). It causes encephalitis in human and horses, and may lead... (Review)
Review
Japanese encephalitis (JE) is a vector-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). It causes encephalitis in human and horses, and may lead to reproductive failure in sows. The first human encephalitis case in Malaya (now Malaysia) was reported during World War II in a British prison in 1942. Later, encephalitis was observed among race horses in Singapore. In 1951, the first JEV was isolated from the brain of an encephalitis patient. The true storyline of JE exposure among humans and animals has not been documented in Malaysia. In some places such as Sarawak, JEV has been isolated from mosquitoes before an outbreak in 1992. JE is an epidemic in Malaysia except Sarawak. There are four major outbreaks reported in Pulau Langkawi (1974), Penang (1988), Perak and Negeri Sembilan (1998-1999), and Sarawak (1992). JE is considered endemic only in Sarawak. Initially, both adults and children were victims of JE in Malaysia, however, according to the current reports; JE infection is only lethal to children in Malaysia. This paper describes a timeline of JE cases (background of each case) from first detection to current status, vaccination programs against JE, diagnostic methods used in hospitals and factors which may contribute to the transmission of JE among humans and animals in Malaysia.
Topics: Animals; Disease Outbreaks; Encephalitis, Japanese; Humans; Japanese Encephalitis Vaccines; Malaysia; Vaccination
PubMed: 29856986
DOI: 10.1016/j.actatropica.2018.05.017 -
Annali Di Igiene : Medicina Preventiva... 2024Japanese encephalitis, caused by the JE virus transmitted by mosquitoes, is the most common type of epidemic encephalitis in Asia. It is endemic in most of South and... (Review)
Review
Japanese encephalitis, caused by the JE virus transmitted by mosquitoes, is the most common type of epidemic encephalitis in Asia. It is endemic in most of South and Southeast Asia, but the number of cases can vary greatly between areas. While many infections do not lead to disease, the symptomatic cases can be very severe and life-threatening. It mainly affects children, whereas adults are generally immune to the disease due to either being infected in childhood or receiving vaccination. However, individuals who are not immune, such as travelers from non-endemic countries, are susceptible to the disease when exposed to the virus for the first time, regardless of age. Without antiviral treatment options, vaccination is the only strategy to establish effective protection against Japanese encephalitis.
Topics: Adult; Child; Animals; Humans; Encephalitis, Japanese; Asia; Vaccination; Culicidae
PubMed: 38436079
DOI: 10.7416/ai.2024.2616 -
Journal of Travel Medicine May 2018Japanese encephalitis (JE) is a viral disease predominantly located in South East Asia and commonly associated with transmission between amplifying hosts, such as pigs,... (Review)
Review
BACKGROUND
Japanese encephalitis (JE) is a viral disease predominantly located in South East Asia and commonly associated with transmission between amplifying hosts, such as pigs, and the mosquito Culex tritaeniorhynchus, where human infection represents a dead end in the life cycle of the virus. The expansion of JE beyond an Asiatic confine is dependent on a multitude of complex factors that stem back to genetic subtype variation. A complex interplay of the genetic variation and vector competencies combine with variables such as geography, climate change and urbanization.
METHODS
Our understanding of JE is still at an early stage with long-term longitudinal vector surveillance necessary to better understand the dynamics of JE transmission and to characterize the role of potential secondary vectors such as Cx. pipiens and Cx. bitaeniorhynchus. The authors review the vectors indicated in transmission and the ecological, genetic and anthropological factors that affect the disease's range and epidemiology.
CONCLUSION
Monitoring for the presence of JE virus in mosquitoes in general can be used to estimate levels of potential JE exposure, intensity of viral activity and genetic variation of JEV throughout surveyed areas. Increased surveillance and diagnosis of viral encephalitis caused by genotype 5 JE virus is required in particular, with the expansion in epidemiology and disease prevalence in new geographic areas an issue of great concern. Additional studies that measure the impact of vectors (e.g. bionomics and vector competence) in the transmission of JEV and that incorporate environmental factors (e.g. weekly rainfall) are needed to define the roles of Culex species in the viral pathogenesis during outbreak and non-outbreak years.
Topics: Animals; Asia; Climate Change; Culex; Disease Outbreaks; Encephalitis Virus, Japanese; Encephalitis, Japanese; Genome; Humans; Meat-Packing Industry; Mosquito Vectors; Poultry; Prevalence; Swine
PubMed: 29718435
DOI: 10.1093/jtm/tay009